Create a function in JavaScript

In JavaScript, there are three primary ways to create a function: Function Declaration, Function Expression, and Arrow Function.

1. Function Declaration:

Example Code:

function sayHello() {
  console.log("Hello, World!");
}

Characteristics: One of the major features of function declarations are hoisted to the top of their scope. Which mean, you can call a function before it’s defined in the code, and it will still work.

2. Function Expression:

Example Code:

const add = function(a, b) {
  return a + b;
};
console.log(add(5, 3)); // Outputs: 8

Characteristics: Function expressions are NOT hoisted to the top of their scope. Which mean, you can NOT call a function before it’s defined in the code.

Function expressions are commonly used as Callbacks arguments to other functions or in situations where you need to define a function dynamically.

3. Arrow Function (ES6+):

More concise syntax for writing functions, especially for small, simple functions. Arrow functions are always anonymous.

Example Code:

const multiply = (a, b) => a * b;
console.log(multiply(4, 5)); // Outputs: 20

Characteristics: Arrow functions don’t have their own this context.

Example of Anonymous Function:

const multiply = function(a, b) {
  return a * b;
};

console.log(multiply(4, 5)); // Outputs: 20

In this case, the anonymous function has no name, but it is stored in the multiply variable, so you can call it through the variable.

Summary:

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