Both exceptions and errors in java is child of thorwable

Condition may occur during execution, you should not try to catch them. Example - OutOfMemory

Exception are the abbormal condition which may come during program execution when exception occurs, it interrupts normal flow of execution and jumps to handler, if no handler is defined it will bubble out till it reaches to JVM,

To handle exception we use try -catch

class A {
    public void doSomething(){
        try{
            
        }catch (Exception ex){
            //optional if finally added 
        }
        finally {
            // Optional 
        }
    }
}

Java 8 support functional programming using lambdas. Concept of Functional. Functional Interface is the with only one abstract method

Example

@FunctionalInterface
public interface Run {
    void run();
}

Lambdas expressions are the inline implementation of the methods in functional interface.