🕑 Understanding Asynchronous Callbacks in JavaScript

Asynchronous Callbacks provide a key feature that allows JavaScript to call functions at different times. Since JavaScript is a single-threaded language, it can only run one operation at a time in order. If you need a function to wait for data or not execute immediately, an asynchronous callback can help.

Example: `setTimeout()`
`setTimeout()` is a simple but powerful function that delays executing a block of code within another function, running it only when necessary.

<pre class="preFormatted"><code class="codeFormatted">
setTimeout(() => {
  console.log("This message is delayed by 2 seconds");
}, 2000);
</code></pre>

In the example above, the callback function inside `setTimeout()` is delayed by 2 seconds before executing.

✨ Real-world Scenario:
Consider when a client logs in to a webpage; the main content begins loading in immediately. However, elements like the contact list, profile picture, comments, or ads might take longer to load because they require data from the server.

With asynchronous callbacks, the page can display the primary content without waiting for all server data to arrive. This ensures a smoother experience for the user, as they can access the page’s core content first, while other parts load as the data becomes available.