Function Types in JavaScript

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JavaScript has several types of functions, including:

Function Declarations:

Function declarations define named functions with optional parameters and a function body.
Example:

function myFunction(parameter1, parameter2) {
  // function body
}

Function Expressions:

Function expressions create functions anonymously and assign them to variables.
Example:

var myFunction = function(parameter1, parameter2) {
  // function body
};

Arrow Functions:

Arrow functions are a concise way to write function expressions in ES6. They have a simplified syntax and a lexical this binding.
Example:

const myFunction = (parameter1, parameter2) => {
  // function body
};

Immediately Invoked Function Expressions (IIFE):

IIFEs are functions that are executed immediately after they are defined. They are useful for creating private variables and functions.
Example:

(function() {
  // function body
})();

Methods:

Methods are functions that are defined as properties of objects. They can be called on the object they belong to using the dot notation.
Example:

var myObject = {
  myMethod: function(parameter1, parameter2) {
    // function body
  }
}; myObject.myMethod(parameter1, parameter2);

Callback Functions:

Callback functions are functions that are passed as arguments to another function and are executed when the function completes its task.
Example:

function myFunction(callback) {
  // function body
  callback();
}

myFunction(function() {
  // callback function body
});