Understanding JavaScript Callbacks

JavaScript callbacks are an essential concept that allows functions to be passed as arguments and executed later. They play a significant role in asynchronous programming, ensuring that specific code runs after particular tasks are completed.

?? What is a Callback?

A callback is simply a function passed as an argument to another function. Once the first function completes its task, it calls (or executes) the callback function.

function fetchData(callback) {
  console.log('Fetching data...');
  setTimeout(() => {
    console.log('Data fetched!');
    callback('Fetched Data');
  }, 2000);
}

function displayData(data) {
  console.log(`Displaying: ${data}`);
}

fetchData(displayData);        

???? Why Use Callbacks?

• Asynchronous Operations: Callbacks are ideal for handling tasks like API requests, file reading, or database operations.
• Control Flow Management: They allow functions to execute in a particular sequence.
• Avoid Blocking: Prevents blocking the main thread while waiting for operations to complete.

? Callback Hell (Pyramid of Doom)

When callbacks are nested within each other, it can lead to unreadable and unmanageable code, also known as Callback Hell.

? Solution: Using Promises or Async/Await

To avoid Callback Hell, you can use Promises or Async/Await for cleaner and more readable code.