https://nodejs.org/en/docs/

• GLOBALS - NO window

• __dirname - path to current directory

• __filename - file name

• require - function to use modules (Common JS)

• module - info about current module (file)

  • https://nodejs.org/api/modules.html
  • OS,
  • PATH,
  • FS(File System),
  • HTTP

• process - info about env where the program is being executed.

https://www.npmjs.com/

• npm - global command, comes with node

• Run npm --version .

• Local dependency - use it in any object

• Run npm i 'packageName' to install any package.

• Run npm i 'packagename' -D OR --save-d to install as dev dependencies.

• Global dependency - use it in any project

• RUn npm install -g 'packageName'.

• package.json - manifest files(stores imp info about project).

• Manual approach ( create package.json in the root, create properties)

  • npm init (step-by-step)
  • npm init -y (everything default)
    • e.g. package lodash npm i lodash in terminal.
    • Run npm install after cloning the projects and it will install all dependencies.

• To uninstall run npm uninstall 'packagename'.

• Event-driven programming
• Used heavily in Node.js
• on - listen for an event
• emit - emit an event
• possible in server side
• listen for specific events and register functions that will execute in response for those events.
• Once events takes place callback func fires.

• Used to read or write sequentially.
• writable, Readable, Duplex, Transform.
• Extend events emitter class.
• data is read in chunks each for 64KB.