The following is based on a conversation with ChatGPT, so the information may not be totally accurate.

• The Missing Link: Code, Computer & Output
  • What is programming?
  • What is a computer?
  • How does a programming language become 0s and 1s?
  • How do 0s and 1s become things we see on a computer screen?
  • What are these 0s and 1s?
  • If text editors and IDEs are like programs that make programs, how were the very first ones developed?
  • Prior to IDEs, how did people enter code into a computer?
• History of computing
• Fundamentals of programming
  • What are the differences between compiled and interpreted languages?
  • What are the differences between functional and procedural programming?
  • What are data types?
  • What is the stack and the heap?
  • What is a function?
  • What are variables?
  • What is a pointer?
  • What is compilation?
  • What are some good languages to learn programming fundamentals?
  • What is the difference between back-end and front-end?
  • What are some back-end and front-end languages?
  • What is a hello world program?
• Becoming a programmer
  • How to start?
  • What does it take to be a programmer?
  • How can freelancing give you more freedom to work on other things?
  • How to become a freelancer?

It might help to first understand at a high level the link between the code, the computer and the output.

Computer programming is the process of designing and building sets of instructions that a computer can follow to perform specific tasks or functions. It involves using programming languages, which are like specialised languages that computers can understand, to write code. The code is a series of commands and algorithms that tell the computer how to execute a particular operation.

In simpler terms, it's akin to writing a detailed recipe for a chef, but in this case, the "chef" is a computer. The programmer is the one who writes the recipe, specifying each step and detail, and the computer follows those instructions to carry out a desired outcome. This could range from creating software applications, websites, or even controlling the behaviour of hardware devices.

A computer is an electronic device that processes and stores data to perform tasks according to a set of instructions. It's like a super-fast and really smart machine that can handle a lot of information at once. Computers come in different forms, from desktops and laptops to tablets and smartphones.

At its core, a computer has a central processing unit (CPU) that acts as the brain, carrying out instructions and calculations. It also has memory to store information temporarily, and storage for keeping data more permanently. Computers can connect to the internet, allowing them to access a vast amount of information and communicate with other computers.

At its most fundamental level, computers operate using binary code, which consists of sequences of 0s and 1s. This binary system is the foundation of digital computing and is used to represent and manipulate data in the form of bits (binary digits). Each binary digit, or bit, can represent one of two values: 0 or 1.

In simple terms, a computer is a versatile tool that people use for tasks like writing documents, sending emails, playing games, watching videos, and much more. It can be programmed to do a wide variety of jobs, making it an essential part of our daily lives.

The process of turning code into 0s and 1s involves a compilation or interpretation step, depending on the programming language. Let me break it down:

Programmers write code using high-level programming languages like Python, Java, or C++. These languages are designed to be human-readable and allow programmers to express instructions in a way that makes sense to them.

The next step is either compilation or interpretation. In compilation, a special program called a compiler translates the entire human-readable code into a lower-level language known as machine code, which consists of binary 0s and 1s. This machine code is specific to the computer's architecture.

In interpretation, another program called an interpreter reads and executes the code line by line without producing a separate machine code file. Instead, it translates and runs each line directly.

Regardless of whether the code was compiled or interpreted, the final result is a series of instructions in binary form (0s and 1s). These instructions are then executed by the computer's central processing unit (CPU). The CPU understands and processes these binary instructions to perform the tasks described in the original code.

In essence, the conversion of code to 0s and 1s is an intermediary step in the process of getting a computer to understand and execute the instructions provided by the programmer. This binary representation is the language that computers "speak" and can directly act upon.

The process of how 0s and 1s in a computer are translated into the things we see on a computer screen involves several layers of abstraction and hardware components. Here's a simplified overview:

At the lowest level, information in a computer is represented using binary digits, or bits, which can be either 0 or 1.

The central processing unit (CPU) of a computer interprets and executes instructions stored in memory. These instructions, represented in binary code, manipulate data.

Data and instructions are temporarily stored in the computer's memory (RAM - Random Access Memory) for quick access by the CPU.

In the context of displaying graphics, a dedicated graphics processing unit (GPU) is responsible for rendering images and handling graphical operations.

The GPU maintains a frame buffer, which is a portion of the memory used to store the pixels that make up the image displayed on the screen.

Software interfaces, such as graphics libraries (e.g., DirectX or OpenGL) and application programming interfaces (APIs), allow developers to issue high-level commands for graphical rendering.

The operating system manages the interaction between software applications and hardware components, including the display. It also coordinates the transfer of data between the CPU, GPU, and memory.

Specific drivers for the GPU translate high-level commands from software into low-level commands that the GPU can understand.

The GPU sends the processed graphical data to the monitor through a display interface (e.g., HDMI, DisplayPort). The monitor then converts this data into visible light.

The image on the screen is composed of pixels, each represented by combinations of red, green, and blue (RGB) values. The intensity of each color is determined by the binary data processed by the GPU.

In summary, the 0s and 1s stored in memory are manipulated by the CPU, processed by the GPU, converted into pixel data, and then sent to the monitor for display. The collaboration of hardware components, drivers, and software layers ensures that the binary information is transformed into the visual content we see on the computer screen.

In computers, 0s and 1s are binary digits, often referred to as "bits." The binary system is the fundamental language of computers, and it uses a base-2 numeral system. In this system, each digit, or bit, can have one of two values: 0 or 1.

Here's a brief explanation of how binary digits work in computing:

In the binary system, each digit represents a power of 2. The rightmost bit represents 2^0 (1), the next bit to the left represents 2^1 (2), the next 2^2 (4), and so on. The value of each bit doubles as you move from right to left.

By combining 0s and 1s in different sequences, you can represent a wide range of values. Just like in the decimal system (base-10) where numbers are represented using digits 0 through 9, in the binary system, numbers are represented using digits 0 and 1.

Computers typically process information in groups of bits, commonly organised into bytes. A byte is made up of 8 bits. With 8 bits, you can represent 2^8 (256) different values, ranging from 00000000 to 11111111 in binary.

Computers perform operations using binary arithmetic. This includes addition, subtraction, multiplication, and division, all of which are carried out using combinations of 0s and 1s.

All data in a computer, whether it's numbers, text, images, or instructions, is ultimately represented and processed using 0s and 1s. This binary representation is the foundation of digital computing.

For example, the binary number 1101 represents:

1×2^3 + 1×2^2 + 0 × 2^1 + 1×2^0 = 8 + 4 + 0 + 1 = 13

Understanding binary is fundamental to understanding how computers store, process, and transmit information. While it may seem complex, various programming languages, assemblers, and higher-level abstractions shield most programmers from having to work directly with individual bits and bytes.

The development of assembly language and early tools was driven by the need for a more human-readable and manageable way to program computers. Here's an overview of how assembly language and early tools were developed:

Initially, programmers had to write programs directly in machine code, which consists of binary instructions understood by the computer's central processing unit (CPU). This process was cumbersome and error-prone, as it required an in-depth understanding of the computer's architecture and the ability to work with binary values.

As computers became more complex, there was a need for a more readable and mnemonic representation of machine code instructions. Assembly language was conceived as a symbolic representation of machine code, using mnemonics to represent the individual instructions.

Assemblers were developed to automate the translation of assembly language code into machine code. These programs took human-readable assembly code and converted it into the corresponding binary instructions that the computer could execute. Assemblers made programming more accessible by allowing programmers to work with symbolic instructions rather than raw binary.

Before the development of assemblers, programmers had to input machine code directly into computers using methods that involved low-level interactions. Here are some of the early methods used:

Programmers would punch holes in punch cards to represent machine code instructions. Each card typically represented one line of code, and the pattern of holes corresponded to the binary representation of the instructions. These punch cards were then fed into card readers connected to the computer.

Similar to punch cards, paper tapes were used for input. Programmers would create a series of holes in a long strip of paper tape to encode the machine code. The tape would then be fed into a tape reader attached to the computer.

Some early computers had panels with toggle switches that represented binary digits (0s and 1s). Programmers manually set these switches to input the binary machine code directly into the computer's memory. This process required a deep understanding of the computer's architecture.

In certain cases, computers had front panels with lights and switches that allowed programmers to enter machine code directly. This method involved toggling switches to set the memory address and entering the binary machine code manually.

Some early computers used plugboards or patch panels. Programmers would physically plug wires into specific sockets to create the machine code instructions. This was a somewhat more flexible but still labor-intensive method.

In the absence of specialised tools, some programmers resorted to manually writing the binary machine code on paper, and operators or programmers would then carefully enter it into the computer.

These methods required a high level of precision and knowledge of the computer's architecture. They were time-consuming, error-prone, and not very user-friendly. The development of assembly languages and assemblers significantly improved the programming process by allowing programmers to work with symbolic representations of machine code, making coding more accessible and less error-prone.

From electricity to bits

What is a computer?

The history of computing is a fascinating journey that spans centuries and involves various innovations and milestones. Here's a brief overview:

Humans have used various tools for calculation, such as the abacus in ancient times and the astrolabe in the medieval period, to perform mathematical tasks.

Inventors like Blaise Pascal and Gottfried Wilhelm Leibniz created mechanical calculators in the 17th century. Charles Babbage conceptualised the design of a mechanical, programmable computer known as the Analytical Engine in the 1830s, although it was never fully built during his lifetime.

Ada Lovelace, working with Charles Babbage, wrote the first algorithm intended for processing on the Analytical Engine, earning her the title of the world's first programmer.

Telegraph systems used punched cards to transmit messages, an idea later adapted for data processing by Herman Hollerith. Hollerith's punched card system was used for the 1890 U.S. Census and laid the foundation for tabulating machines and early computing.

The 1930s and 1940s saw the development of electromechanical computers. Konrad Zuse built the Z3 in Germany, considered the world's first programmable digital computer. Meanwhile, Alan Turing developed theoretical concepts of computation and the Turing Machine.

The Electronic Numerical Integrator and Computer (ENIAC), completed in 1945, was one of the earliest electronic general-purpose computers. UNIVAC I, introduced in 1951, became the first commercially produced computer.

The invention of the transistor in the 1950s and the development of integrated circuits in the 1960s revolutionised computing by making electronic components smaller, faster, and more reliable.

The advent of microprocessors, such as the Intel 4004, led to the development of affordable personal computers. Companies like Apple and Microsoft were founded in the mid-1970s, marking the beginning of the personal computer era.

The 1980s and 1990s brought the rise of graphical user interfaces (GUIs) with systems like Apple's Macintosh and Microsoft Windows. The development of the World Wide Web in the 1990s transformed communication and information sharing globally.

The 2000s witnessed the rise of mobile computing with smartphones and tablets. Cloud computing became prevalent, enabling remote storage and access to data. Advances in artificial intelligence, machine learning, and quantum computing are shaping the current landscape.

The history of computing is characterised by continuous innovation, from early mechanical devices to today's highly interconnected and powerful digital systems. The journey has been driven by the contributions of countless inventors, engineers, and visionaries across different eras.

A brief history of computers

History of computers: A brief timeline

Compiled languages and interpreted languages are two different approaches to executing code. Here are the key differences between them:

In compiled languages, the source code is translated into machine code or an intermediate code by a compiler before the program is run.

The compiled code is executed directly by the computer's hardware or by a virtual machine that understands the generated intermediate code.

Typically, compiled languages offer faster execution because the entire program is translated into machine code before execution, optimising it for the specific hardware.

Examples of compiled languages include C, C++, Rust, and Swift.

In interpreted languages, the source code is read and executed line by line by an interpreter at runtime. The interpreter translates and executes the code on-the-fly.

The original source code is not translated into machine code beforehand; instead, it is interpreted and executed directly.

Interpreted languages may have a slightly slower execution compared to compiled languages because the translation happens during runtime.

Examples of interpreted languages include Python, JavaScript, Ruby, and PHP.

Some languages, like Java and C#, use a hybrid approach. They are compiled into an intermediate bytecode, and this bytecode is executed by a virtual machine (Java Virtual Machine for Java, Common Language Runtime for C#). This combines elements of both compilation and interpretation.

• Advantages: Faster execution, optimised for specific hardware.
• Disadvantages: Longer build times, platform-dependent executables.

• Advantages: Platform-independent code, shorter development cycles.
• Disadvantages: Slower execution, dependencies on interpreters.

In summary, the main distinction lies in when the translation from source code to machine code occurs. Compiled languages perform this translation before the program runs, while interpreted languages do it at runtime. Each approach has its strengths and weaknesses, and the choice between them often depends on factors like performance requirements, development speed, and platform independence.

Functional programming and procedural programming are two different programming paradigms, each with its own set of principles and approaches. Here are the key differences between them:

In functional programming, the primary building blocks are functions. Functions are treated as first-class citizens, meaning they can be passed as arguments to other functions, returned as values from other functions, and assigned to variables.

Functional programming emphasises immutability, where once a data structure is created, it cannot be changed. Instead of modifying existing data, new data structures are created.

Functional programming aims to minimise or eliminate side effects. Functions should only depend on their inputs and produce a result without causing changes outside the function.

Code in functional programming tends to be more declarative, expressing what should be done rather than explicitly detailing how to do it.

Recursion is often used for iteration instead of traditional loop constructs.

Examples of functional programming languages include Haskell, Lisp, and functional features in languages like JavaScript and Python.

// Example: Functional Programming in JavaScript

// Function to calculate the square of a number
const square = (x) => x * x;

// Function to calculate the sum of squares for an array of numbers
const sumOfSquares = (numbers) => numbers.map(square).reduce((acc, val) => acc + val, 0);

// Sample array of numbers
const numbers = [1, 2, 3, 4, 5];

// Calculate and print the sum of squares
const result = sumOfSquares(numbers);
console.log("Sum of Squares:", result);

Procedural programming is based on procedures (functions or routines) that operate on data. Procedures describe a sequence of steps to achieve a specific task.

Data can be modified during the execution of the program. Variables can be assigned new values, and data structures can be changed in-place.

Procedural programming allows side effects, where functions can modify external states or have an impact beyond their return values.

Code in procedural programming tends to be more imperative, specifying how to perform tasks with explicit steps.

Iteration is often done using loop constructs (e.g., for, while) for repetitive tasks.

Examples of procedural programming languages include C, Pascal, and early versions of Fortran.

# Example: Procedural Programming in Python

# Function to calculate the square of a number
def square(x):
    return x * x

# Function to calculate the sum of squares for a list of numbers
def sum_of_squares(numbers):
    total = 0
    for num in numbers:
        total += square(num)
    return total

# Sample list of numbers
numbers = [1, 2, 3, 4, 5]

# Calculate and print the sum of squares
result = sum_of_squares(numbers)
print("Sum of Squares:", result)

Many languages support both functional and procedural programming paradigms, allowing developers to choose the style that best fits the problem at hand. For example, Python supports both procedural and functional programming features.

The choice between functional and procedural programming often depends on the nature of the problem, the team's expertise, and the desired characteristics of the code (e.g., readability, maintainability, performance). Some developers even use a mix of both paradigms in their code, leveraging the strengths of each when appropriate.

In programming, a data type is a classification that specifies which type of value a variable can hold or what type of data a function can return. Data types are essential for defining the nature of the data that a program manipulates. They help determine the operations that can be performed on the data and the storage requirements for that data. Common data types include:

Represents whole numbers without any fractional parts. Examples: 1, -5, 100.

Represents numbers with a decimal point or in exponential form. Examples: 3.14, -0.001, 2.5e3 (scientific notation).

Similar to a float but with higher precision. Examples: 3.14159, -123.456.

Represents a single character. Examples: 'a', '5', '$'.

Represents a sequence of characters. Examples: "Hello, World!", "12345".

Represents a binary value, typically true or false. Used for logical operations. Examples: true, false.

Represents a collection of elements of the same type. Examples: [1, 2, 3], ["apple", "orange", "banana"].

Similar to an array but can store elements of different data types. Examples: (1, "apple", 3.14).

A dynamic array that can grow or shrink in size. Examples: [1, 2, 3], ["apple", "orange", "banana"].

Represents an unordered collection of unique elements. Examples: {1, 2, 3}, {"apple", "orange", "banana"}.

Represents a collection of key-value pairs. Examples: {"name": "John", "age": 25}, {1: "one", 2: "two"}.

Represents an instance of a user-defined class, encapsulating both data and behaviour. Examples: instances of custom classes.

Represents a block of reusable code that performs a specific task. Examples: functions or methods.

Represents the absence of a value or a null reference. Examples: null (in languages like Java, C#), None (in Python).

Represents a memory address, often used for referencing other variables or objects. Examples: memory address 0x0012ABCD.

The specific data types available and their characteristics may vary between programming languages. Understanding data types is crucial for writing efficient and error-free code, as it ensures that variables are used appropriately and operations are performed consistently.

The heap and the stack are two regions of a computer's memory that serve different purposes in the execution of a program. They are used for storing different types of data and have distinct characteristics:

The stack is a region of memory that operates in a last-in, first-out (LIFO) fashion. It is used for storing local variables, function call information, and control flow data. Each function call in a program creates a new stack frame, which contains information like local variables, function parameters, and the return address. When a function completes, its stack frame is popped off the stack.

Memory allocation and deallocation in the stack are fast and deterministic because of its simple structure. The stack is typically limited in size, and exceeding this limit can lead to a stack overflow.

The heap is a region of memory used for dynamic memory allocation. It is not organised in a structured way like the stack and allows for flexible memory allocation and deallocation. Data stored in the heap persists beyond the scope of individual functions and can be accessed globally.

Manual memory management is often required for the heap, meaning the programmer is responsible for allocating and deallocating memory as needed. Improper memory management can lead to memory leaks or fragmentation. The heap is typically larger than the stack, but memory access in the heap may be slower than on the stack due to its less organised structure.

• Storing local variables and function call information.
• Managing the order of function calls and returns.
• Limited in size, and memory is automatically reclaimed when a function exits.

• Dynamic memory allocation for data that needs to persist beyond the scope of individual functions.
• Allocating memory for data structures of varying sizes.
• The programmer must manually allocate and deallocate memory.

These languages provide explicit control over both the stack and the heap, giving the programmer more responsibility for memory management.

These languages use automatic memory management (garbage collection) for the heap, making memory allocation and deallocation less explicit and automatic.

Understanding the differences between the stack and the heap is crucial for writing efficient and reliable programs, especially in languages that provide manual memory management. It also influences how functions are called, variables are stored, and memory is managed during the execution of a program.

In programming, a function is a reusable block of code that performs a specific task or a set of tasks. Functions are designed to be modular and self-contained, allowing developers to organise code into manageable and reusable units. Functions are a fundamental concept in most programming languages and play a crucial role in structuring code and promoting code reuse.

Here are key characteristics and components of a function:

A function is identified by a name that is used to call or invoke it. The name should be descriptive and indicative of the function's purpose.

Functions can accept input values known as parameters or arguments. These values provide information that the function may need to perform its task. Parameters are listed within parentheses in the function declaration.

A function may produce a result, known as the return value. This value is specified using the return keyword in the function body. Functions don't always have to return a value; some are designed to perform actions without producing a result.

The function body contains the set of instructions that define what the function does. It is enclosed within curly braces {} in many programming languages.

To execute a function, it must be called or invoked using its name and, if applicable, providing the required arguments. The function's code is then executed, and it may return a result.

Functions often have their own scope, meaning the variables declared within a function are typically local to that function and not accessible from outside.

// Function declaration with parameters
function addNumbers(a, b) {
  // Function body
  var sum = a + b;
  
  // Return the result
  return sum;
}

// Function invocation with arguments
var result = addNumbers(5, 3);

// 'result' now holds the value 8

In this example, addNumbers is a function that takes two parameters (a and b), adds them together, and returns the result. The function is then called with arguments 5 and 3, and the result is stored in the variable result.

Functions are essential for organising code, promoting code reuse, and breaking down complex problems into smaller, more manageable parts. They are a core concept in procedural, object-oriented, and functional programming paradigms.

In programming, a variable is a symbolic name or identifier associated with a memory location that stores data. Variables allow programmers to use meaningful names to represent values or data that can be manipulated and referenced in a program. They serve as containers for storing and managing information within a computer's memory.

Here are key characteristics and concepts related to variables:

To use a variable, it must be declared, specifying its name and optionally its data type. The declaration informs the compiler or interpreter about the existence of the variable.

// Variable declaration in Java
int age;

After declaration, a variable can be initialised with an initial value. Initialisation assigns a value to the variable, and it typically occurs using the assignment operator =.

// Variable initialisation in Java
age = 25;

Declaration and initialisation can be combined in a single statement:

// Declaration and initialisation in one statement
int age = 25;

Variables have data types that define the kind of data they can store. Common data types include integers, floating-point numbers, characters, booleans, and more.

# Variable declaration and initialisation in Python
name = "John"
age = 30

Variables must adhere to naming rules defined by the programming language. Generally, names should start with a letter, may include numbers and underscores, and shouldn't be reserved words.

// Variable declaration and initialisation in JavaScript
let message = "Hello, World!";

The scope of a variable refers to the region of the program where the variable is accessible. Variables may be local to a specific function, global to the entire program, or have other levels of visibility.

Variables can change their values during the execution of a program. This is a fundamental aspect of dynamic programming languages.

# Variable reassignment in Python
age = 30
age = age + 1  # Incrementing age

Variables are often used in expressions, allowing for computation and manipulation of values.

// Using variables in an expression in Java
int x = 5;
int y = 3;
int sum = x + y;  // sum is now 8

Variables are a fundamental concept in programming, allowing developers to store, manipulate, and reference data efficiently. They provide a way to work with values in a symbolic and human-readable manner, enhancing the clarity and maintainability of code.

A pointer is a variable in programming that stores the memory address of another variable. In simpler terms, a pointer "points to" the memory location where a specific piece of data is stored. Pointers are a fundamental concept in languages that support direct memory manipulation, such as C and C++. Here are key aspects of pointers:

Pointers are declared using an asterisk (*) before the variable name. For example:

int *ptr;  // Declares a pointer to an integer

Pointers need to be initialized with the memory address of a variable. This is typically done using the address-of operator (&):

int num = 10;
int *ptr = #  // Initializes the pointer with the address of 'num'

Dereferencing a pointer means accessing the value stored at the memory address it points to. This is done using the dereference operator (*):

int num = 10;
int *ptr = #  // Initializes the pointer with the address of 'num'
printf("Value at the memory location: %d", *ptr);  // Prints the value stored in 'num'

Pointers can be incremented or decremented to navigate through memory locations. The size of the increment or decrement depends on the type of data the pointer points to. For example:

int arr[3] = {10, 20, 30};
int *ptr = arr;  // Points to the first element of 'arr'
printf("%d", *(ptr + 1));  // Prints the value at the second element of 'arr'

Pointers can be assigned a special value called NULL (or nullptr in C++) to indicate that they do not point to a valid memory address. This is often used to check if a pointer is valid before dereferencing it.

Pointers are commonly used in dynamic memory allocation, where memory is allocated and deallocated during the program's execution using functions like malloc and free (in C) or new and delete (in C++).

Here's a simple example in C:

#include <stdio.h>

int main() {
    int num = 42;
    int *ptr = &num;  // Pointer 'ptr' holds the address of 'num'

    printf("Value of 'num': %d\n", num);
    printf("Address of 'num': %p\n", (void*)&num);
    printf("Value at the address pointed by 'ptr': %d\n", *ptr);

    return 0;
}

In this example, ptr holds the memory address of num, and the *ptr expression dereferences the pointer, allowing access to the value stored at that memory address. Pointers are powerful but require careful use to avoid issues like memory leaks or undefined behavior.

Compilation is the process of translating source code written in a high-level programming language into machine code or an intermediate code that can be executed by a computer. The primary goal of compilation is to convert human-readable code into a form that the computer's hardware can understand and execute efficiently. The process involves several steps:

The source code is the program written by a programmer in a high-level programming language like C, C++, Java, or Python. This code is written in a way that is easy for humans to understand and is often independent of the specific hardware architecture.

The compilation process is typically performed by a compiler, which is a specialised program designed for this purpose. The compiler reads the entire source code and translates it into an equivalent program in machine code or an intermediate code.

The first step of the compilation process involves breaking down the source code into smaller units called tokens. This step is performed by a component called a lexer or scanner.

The parser analyses the structure of the source code, checking that it adheres to the syntax rules of the programming language. It creates a hierarchical structure called the abstract syntax tree (AST).

The compiler performs semantic analysis to ensure that the source code makes sense in terms of the language's semantics. It checks for logical errors that may not be apparent from the syntax alone.

In some cases, especially in languages like Java and C#, the compiler generates an intermediate code rather than machine code directly. This intermediate code is often platform-independent and is later executed by a virtual machine.

The compiler may perform various optimisations to improve the efficiency of the generated code. Optimisation techniques aim to reduce the execution time or memory usage of the program.

The compiler generates the final executable code based on the intermediate code or directly from the source code. This code is specific to the target machine architecture.

In languages that support separate compilation (e.g., C and C++), the linking phase combines multiple compiled files into a single executable or library. This involves resolving references between different parts of the program.

The final output of the compilation process is an executable file that can be run on the target computer. This file contains the machine code or intermediate code needed to execute the program.

Compilation is a crucial step in the software development process, allowing programmers to write code in a high-level language and then execute it on various hardware platforms. It helps improve code efficiency, ensures correctness, and enables the creation of software that can be distributed and run on different systems.

Choosing a programming language to learn programming fundamentals depends on several factors, including your goals, interests, and the applications you are interested in developing. However, some languages are particularly well-suited for beginners due to their simplicity, readability, and widespread use in educational contexts. Here are a few recommendations:

Python is often recommended as a first programming language for beginners. It has a clean and readable syntax, making it easy to understand. Python is versatile and widely used in various domains, including web development, data science, artificial intelligence, and more. Many educational resources and beginner-friendly tutorials are available for learning Python.

If you are interested in web development, JavaScript is an excellent choice. It's a fundamental language for front-end web development and allows you to build interactive websites. JavaScript is widely supported by browsers, and you can quickly see the results of your code in a web browser.

Scratch is a visual programming language designed for beginners, especially kids. It uses a drag-and-drop interface, making it easy to create interactive stories, games, and animations. Scratch is a great way to grasp programming concepts without the need to type out code.

Java is known for its portability and is often used for building enterprise-level applications. Learning Java provides a strong foundation in object-oriented programming (OOP) concepts, making it beneficial for understanding principles that apply to other languages.

Ruby is valued for its simplicity and readability. It's often used for web development, and the Ruby on Rails framework is popular for building web applications. Ruby's syntax is straightforward, making it beginner-friendly.

Developed by Microsoft, C# is widely used for building Windows applications, games using Unity, and web applications using ASP.NET. It has a syntax similar to Java and is known for its readability and strong integration with the .NET framework.

It's important to note that the fundamentals of programming—such as variables, loops, conditionals, functions, and data structures—are consistent across most programming languages. Once you grasp these concepts in one language, transitioning to others becomes easier. Additionally, consider the types of projects you are interested in working on, as different languages are more suitable for specific applications (e.g., mobile app development, data analysis, web development).

In addition to this, I would highly suggest trying to write a program in C!

The terms "back-end" and "front-end" refer to different parts of a software application, each responsible for distinct aspects of the user experience and overall functionality. Here's an overview of the key differences between back-end and front-end development:

Front-end development focuses on the user interface—the visual and interactive aspects of a software application that users directly interact with.

The code for front-end development runs on the client-side, which is the user's web browser or device. It is responsible for rendering and displaying content.

Common front-end technologies include HTML for structure, CSS for styling, and JavaScript for interactivity. Front-end frameworks and libraries like React, Angular, and Vue.js are also used to streamline development.

Front-end developers ensure that the user interface is responsive, visually appealing, and provides a positive user experience across different devices and screen sizes.

Back-end development involves server-side programming, which means the code runs on the server (remote computer) that hosts the application or website.

Back-end development manages data storage, retrieval, and processing. It handles business logic, database interactions, authentication, and other server-side operations that are not visible to the user.

Back-end development commonly involves using server-side languages like Python, Ruby, Java, PHP, or Node.js. Frameworks like Django (Python), Ruby on Rails (Ruby), and Express (Node.js) expedite back-end development.

Back-end developers implement security measures to protect data and ensure secure communication between the client and server. Authentication, authorisation, and data encryption are key considerations.

Ensuring that the back-end infrastructure can handle scalability and accommodate a growing number of users is a crucial aspect of back-end development.

Some developers work on both front-end and back-end aspects, and they are referred to as full-stack developers. Full-stack developers have a broad skill set and can contribute to both client-side and server-side development.

• Front-end development is concerned with the user interface, client-side rendering, and user experience.
• Back-end development handles server-side logic, data processing, and communication with databases.
• Collaboration between front-end and back-end developers is essential for building fully functional and cohesive software applications.

In web development, front-end and back-end components work together to create a seamless user experience, with each aspect playing a critical role in the overall functionality of the application.

Front-End and Mobile Development Languages and Frameworks:

Used for creating the structure and layout of web pages. Essential for both front-end web development and mobile development.

Used for styling and formatting the visual presentation of HTML elements. Crucial for defining the look and feel of both web and mobile interfaces.

A versatile scripting language for adding interactivity to web pages. Essential for front-end web development and widely used in mobile development frameworks.

A superset of JavaScript with static typing. Enhances JavaScript with features that aid in large-scale application development. Used in both front-end and mobile development.

A JavaScript library for building user interfaces. Widely used for creating interactive and reusable UI components in both web and mobile development, especially with React Native for mobile.

A TypeScript-based front-end framework developed by Google. Used for building dynamic single-page applications and mobile apps with frameworks like Ionic.

A progressive JavaScript framework for building user interfaces. Known for its simplicity and ease of integration, Vue.js is used in both front-end web development and mobile app development.

The programming language developed by Apple for iOS and macOS app development. Used with the UIKit and SwiftUI frameworks for building native iOS applications.

A modern programming language for developing Android applications. Kotlin has become the preferred language for Android development, offering improved conciseness and safety.

Java is traditionally used for Android app development. While Kotlin has gained popularity, Java is still prevalent, and many existing Android projects are written in Java.

Flutter is a UI toolkit developed by Google for building natively compiled applications for mobile, web, and desktop from a single codebase. Dart is the language used for Flutter development.

A JavaScript framework for building mobile applications that can run on both iOS and Android platforms. It allows developers to use React to build mobile apps with a single codebase.

A cross-platform mobile app development framework that uses C#. Xamarin allows developers to create native apps for iOS, Android, and Windows using a single codebase.

Choosing the right language or framework for mobile development often depends on the platform (iOS, Android, or cross-platform) and the developer's familiarity with the technology. Front-end developers interested in mobile development can leverage their existing skills in HTML, CSS, and JavaScript when working with frameworks like React Native or Flutter.

A "Hello, World!" program is a simple and traditional program that is often used as the first program when learning a new programming language or environment. The purpose of the "Hello, World!" program is to demonstrate the basic syntax of the language and verify that the development environment is correctly set up.

The program typically prints the message "Hello, World!" to the console or screen. Despite its simplicity, the "Hello, World!" program is a fundamental step for beginners to get acquainted with the basic structure of a program in a specific language.

Here are examples of "Hello, World!" programs in several programming languages:

print("Hello, World!")

console.log("Hello, World!");

public class HelloWorld {
    public static void main(String[] args) {
        System.out.println("Hello, World!");
    }
}

#include <iostream>

int main() {
    std::cout << "Hello, World!" << std::endl;
    return 0;
}

using System;

class Program {
    static void Main() {
        Console.WriteLine("Hello, World!");
    }
}

puts "Hello, World!"

print("Hello, World!")

fun main() {
    println("Hello, World!")
}

Regardless of the programming language, the "Hello, World!" program serves as a starting point for understanding basic syntax, printing output, and running a program in a specific environment. It's a simple yet effective way to introduce someone to the essential concepts of a programming language.

My suggestion would be to:

• Choose an area of interest above (back-end or front end)
• Choose a language based on this area of interest
• Write your first 'hello world!' program!
• Think of a project: perhaps a problem in your life you'd like to solve with a computer program / web page / app, or something simple you'd find fun as a project (e.g. a photo album, a custom shopping list, etc).
• Try to write it from scratch. You'll learn by doing. When you have a question, search the internet. This is very much part of the job, even when you're experienced.
• If you really want to learn deep fundamentals - try to write some programs in C.
• Break your problems down into smaller problems, and move one step at a time. Don't give up!

Becoming a programmer involves a combination of education, skills development, practice, and a problem-solving mindset. Here are the key elements and steps to become a programmer:

Formal Education: While not strictly necessary, many programmers have a formal education in computer science, software engineering, or a related field. A degree can provide a strong theoretical foundation and exposure to various programming languages and concepts. Self-Learning: Many successful programmers are self-taught. There are abundant online resources, tutorials, and courses that cover programming fundamentals. Platforms like Codecademy, Coursera, and freeCodeCamp offer excellent learning materials.

Start with a Beginner-Friendly Language: Begin with a language known for its simplicity and readability, such as Python or JavaScript. These languages are beginner-friendly and widely used. Diversify Skills: As you progress, explore different programming languages based on your interests and the domains you want to work in (web development, data science, mobile app development, etc.).

Programming is fundamentally about solving problems. Practice breaking down problems into smaller, manageable steps and devising logical solutions. Develop algorithmic thinking and practice solving coding challenges on platforms like LeetCode, HackerRank, or CodeSignal.

Apply your skills by working on real projects. This could be a personal website, a small utility tool, or a contribution to an open-source project. Building projects allows you to gain practical experience, apply what you've learned, and showcase your work to potential employers.

Learn how to use version control systems like Git. This is essential for collaboration, code management, and tracking changes in your projects.

Familiarise yourself with the software development lifecycle, including requirements gathering, design, implementation, testing, deployment, and maintenance.

Programming is often a collaborative effort. Learn how to work in teams, communicate effectively, and use tools like GitHub for collaboration.

The field of programming is dynamic, and technologies evolve rapidly. Stay curious, embrace new tools and languages, and continue learning throughout your career.

Connect with other programmers and professionals in the industry. Attend meetups, join online communities, and participate in discussions. Networking can provide valuable insights, mentorship, and potential job opportunities.

Create a portfolio showcasing your projects, skills, and contributions. A strong portfolio can make a significant difference when applying for jobs.

Develop soft skills such as problem-solving, critical thinking, and attention to detail. These skills are crucial for success in the field.

Remember that becoming proficient in programming is a journey, and consistent effort, practice, and a willingness to learn are key factors for success. Whether through formal education or self-learning, the ability to solve problems and create solutions is at the core of being a programmer.

As an addition, I think these things are also good signs:

• Problem solver
• Have determination / persistence to overcome difficulties
• Enjoy puzzles / strategy games (like Chess)
• Are somewhere a bit on the spectrum (if it even exists), e.g. Autism / ADHD

One motivation to become a programmer, is that you can eventually become a freelancer. This is useful if you have other (or artistic) interests, and need time for them.

After working full-time for some years to gain experience, you can try becoming a freelancer.

Freelancing offers several advantages that can provide you with more freedom to work on other things, whether those are personal projects, additional freelance work, or other interests. Here are ways in which freelancing can offer more flexibility and freedom:

As a freelancer, you have the autonomy to set your own work hours. This flexibility allows you to organise your day around your most productive times and accommodate other commitments or interests.

Freelancers have the freedom to choose the projects they want to work on. This enables you to align your work with your interests and expertise, making work more enjoyable.

Many freelance opportunities allow you to work remotely. This means you can choose your workspace, which could be your home, a co-working space, or even a coffee shop. Remote work eliminates the need for a daily commute and provides the freedom to work from anywhere with an internet connection.

Freelancers can take on multiple projects from different clients, leading to diversified income streams. This not only provides financial stability but also gives you the freedom to allocate your time across various projects or allocate time for personal pursuits.

Freelancing doesn't have to be a full-time commitment. Many individuals freelance part-time while maintaining other activities, such as pursuing education, working on personal projects, or exploring other interests.

Freelancing can free up time for personal projects or passion pursuits. Whether it's developing your own software, writing a book, or creating art, freelancing can provide the financial means and schedule flexibility to pursue these endeavours.

As a freelancer, you have control over your work environment. You can create a space that suits your preferences and enhances your productivity. This can contribute to a better work-life balance and the ability to focus on other interests outside of work.

Freelancers need strong time management skills to meet project deadlines. Developing effective time management habits can help you complete work efficiently, leaving more time for other activities.

Freelancers have the freedom to take breaks when needed. Whether it's for personal rejuvenation, travel, or pursuing hobbies, freelancing allows you to structure your time to accommodate necessary breaks.

Freelancers often have the opportunity to integrate work with their personal lives seamlessly. This integration can lead to increased satisfaction and a better balance between work and personal pursuits.

While freelancing can offer more freedom, it's essential to strike a balance and manage your time effectively. Successful freelancers often find ways to leverage their flexibility to pursue a range of interests and projects beyond their freelance work.

Becoming a freelancer involves several steps, from building your skills and creating a portfolio to finding clients and managing your business. Here's a step-by-step guide on how to become a freelancer:

Assess Your Skills: Identify your strengths and skills. What are you good at? What services can you offer? Choose a Niche: Specialising in a specific niche (e.g., web development, graphic design, writing) can help you stand out.

Create a Portfolio: Showcase your work in a professional portfolio. Include examples of projects, case studies, and testimonials if available. Online Presence: Build a personal website or use freelance platforms to create an online presence that potential clients can explore.

Legal Considerations: Depending on your location, you may need to register your freelance business, obtain necessary licenses, and understand tax obligations. Create a Business Plan: Outline your goals, target clients, pricing strategy, and marketing plan.

Research Rates: Research the rates in your industry and location to determine competitive pricing. Consider Expenses: Factor in your time, expenses, and the value you provide when setting your rates.

Create Profiles: Sign up on freelancing platforms like Upwork, Freelancer, Fiverr, or others relevant to your field. Optimize Profiles: Write a compelling bio, showcase your skills, and upload a professional profile picture.

(In addition to this, it's also a good idea to search LinkedIn for recruiters)

Online Presence: Leverage social media, forums, and professional networks to promote your services. Join Freelance Communities: Participate in forums and groups related to your niche. Networking can lead to referrals and opportunities.

Tailor Your Proposals: Customise proposals for each job application. Clearly communicate how you can address the client's needs. Highlight Your Skills: Emphasise your skills, experience, and relevant work samples.

Meet Deadlines: Consistently deliver work on time and communicate proactively if there are delays. Exceed Expectations: Go the extra mile to provide excellent service. Satisfied clients are more likely to hire you again and recommend you.

Ask for Feedback: Request feedback and testimonials from satisfied clients. Positive reviews build credibility. Display Testimonials: Showcase testimonials on your website or freelance platform profiles.

Invoicing: Set up a system for invoicing clients. Clearly outline payment terms and methods. Expense Tracking: Keep track of your business expenses for tax purposes.

Stay Updated: Keep learning and stay updated on industry trends and technologies relevant to your field. Skill Enhancement: Invest time in enhancing your skills and acquiring new ones to remain competitive.

Communication: Maintain clear and prompt communication with clients. Handle Issues Professionally: Address any issues or concerns professionally to maintain a positive client relationship.

Delegate Tasks: As your business grows, consider delegating non-core tasks to focus on high-value work. Raise Rates: Periodically review and adjust your rates based on your experience and the value you provide.

(Depending on your country, you might be required to start a company in order to freelance)

Remember, building a successful freelance career takes time and effort. Consistency, professionalism, and a commitment to delivering quality work will contribute to your success as a freelancer.