𝗧𝘆𝗽𝗲𝘀 𝗼𝗳 𝗝𝗮𝘃𝗮𝗦𝗰𝗿𝗶𝗽𝘁 𝗙𝘂𝗻𝗰𝘁𝗶𝗼𝗻𝘀

📅2 hours ago⏱1 min read

You need to know how functions work to write clean code. JavaScript offers different ways to define and use them.

Here are the main types:

Named Function You give the function a specific name. This makes it easy to call later. Example: function greet() { return "Hello!"; }
Anonymous Function These functions do not have a name. You often assign them to variables. Example: let greet = function() { console.log("Hello!"); };
Function Expression You store a function inside a constant or a variable. Example: const add = function(a, b) { return a + b; };
Arrow Function These provide a shorter syntax. They are part of ES6.

IIFE (Immediately Invoked Function Expression) These run the moment they are defined. You use them to avoid polluting the global scope. Example: (function() { console.log("Run!"); })();
Callback Functions A callback is a function passed into another function as an argument.

Synchronous Callbacks: These run one after another in order.
Asynchronous Callbacks: These run after a task finishes. For example, setTimeout runs a task after a specific delay.

Think of a restaurant. You order food. You give your number. The restaurant calls you when the food is ready. The call is the callback.

Code example: function orderFood(callback) { console.log("Preparing food..."); callback(); }

function callCustomer() { console.log("Food is ready!"); }

orderFood(callCustomer);

Understanding these patterns helps you write better logic.