Async Programming Callback Functions

This page provides a comprehensive overview of callbacks and how to use them effectively in asynchronous programming.

The core concept is to define functions that are executed *after* the initial task is completed, without blocking the main thread.

Here's a quick recap:

Callbacks: Functions passed into other functions to be executed later.
Event Loop: Manages the execution of callbacks, ensuring tasks are executed in the correct order.
Key Characteristics: Asynchronous, non-blocking, handles multiple tasks concurrently.

Let's explore some common use cases:

Fetch Data: A callback function might update the UI after the data is received from the server.
Background Processing: Perform tasks like sending emails or updating notifications without blocking the UI.
Event Handling: Respond to events like user actions.

Example Callback:

`getData()`: A function to retrieve data from the server. Called after the data is received.

`updateUI()`: A function to update the UI based on the received data.

Example Callback:

`sendEmail()`: A function to send an email after data is received.

`updateDisplay()`: A function to update a display on the screen