Functions in JavaScript

Function
Function is a reusable block of code designed to perform a specific task

Eg:
function greet() {
    console.log("Hello, World!");
}

greet(); // Output: Hello, World!

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Function with Parameters
Sometimes we want to pass values to a function. These values are called parameters.

Eg:
function greet(name) {
    console.log("Hello " + name);
}

greet("Pranay"); // Output: Hello Pranay

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Function with Multiple Parameters
A function can have more than one parameter.

Eg:
function add(a, b) {
    console.log(a + b);
}

add(10, 20); // Output: 30

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Function with Return Value
Sometimes we don’t want to print the result directly. Instead, we want the function to send the result back.For that, we use the return keyword.

Eg:
function add(a, b) {
    return a + b;
}

let result = add(10, 20);

console.log(result); // Output: 30

// The return statement ends the function and returns the value.

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Function Expression
A function can also be stored inside a variable.

Eg:
const greet = function() {
    console.log("Hello JavaScript");
};

greet(); // Output: Hello JavaScript

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Arrow Function
Arrow functions are a shorter way to write functions.

**Arrow Function**
Eg:
const greet = () => {
    console.log("Hello JavaScript");
};

greet(); //Output: Hello JavaScript

**Arrow Function with Parameters**
Eg:
const add = (a, b) => {
    return a + b;
};

console.log(add(10, 20)); // Output: 30

// If the function has only one line, we can write it even shorter.

Eg:
const add = (a, b) => a + b;

console.log(add(10, 20)); // Output: 30

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Anonymous Function
A function without a name is called an Anonymous Function.

Eg:
const message = function() {
    console.log("Welcome");
};

message(); // Output: Welcome

// Here, the function has no name and is stored inside the variable message.

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