What is the difference between synchronous and Asynchronous programming in Javascript

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Synchronous programming in JavaScript refers to the traditional way of executing code, where each task is performed one after the other in a sequential manner. In this approach, the program waits for each task to complete before moving on to the next one. This means that if a task takes a long time to execute, it will block the execution of subsequent tasks, causing the program to become unresponsive.

On the other hand, asynchronous programming in JavaScript allows multiple tasks to be executed concurrently without blocking the execution of the program. Instead of waiting for a task to complete before moving on, asynchronous programming uses callbacks, promises, or async/await to handle the completion of tasks. This allows the program to continue executing other tasks while waiting for the completion of asynchronous operations.

Here’s an example to illustrate the difference between synchronous and asynchronous programming in JavaScript:

// Synchronous programming example
console.log("Task 1");
console.log("Task 2");
console.log("Task 3");
// Output: Task 1, Task 2, Task 3 (executed sequentially)
// Asynchronous programming example
console.log("Task 1");
setTimeout(() => {
console.log("Task 2");
}, 2000);
console.log("Task 3");
// Output: Task 1, Task 3, Task 2 (Task 2 executed after a delay of 2 seconds)

In the synchronous example, each task is executed one after the other, and the program waits for each task to complete before moving on to the next one. In the asynchronous example, the program doesn’t wait for the setTimeout function to complete before executing the next task. Instead, it continues executing the next task (console.log("Task 3")) while waiting for the completion of the asynchronous operation (setTimeout). Once the asynchronous operation is complete, the callback function is executed, and the corresponding task (console.log("Task 2")) is executed.

Note: The provided example is in plain JavaScript format. To use it in an HTML file, you can wrap the JavaScript code inside <script> tags within the HTML file.