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Anfal Ratul
Anfal Ratul

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Synchronous and Asynchronous in JavaScript

In JavaScript, synchronous operations block instructions until the task is completed, while asynchronous operations can execute without blocking other operations.

Synchronous JavaScript: In a synchronous operation, each step is performed one after the previous one is finished. This means that it blocks or waits for each operation to complete before moving on to the next.

Asynchronous JavaScript: In an asynchronous operation, operations don’t wait for each other to finish. This means multiple operations can be going on at the same time. When you start an operation, you can move on to another operation before the previous one finishes. This is particularly useful for tasks that take a lot of time, such as requests to servers.

For example, if you have a function that fetches data from a server and it takes two seconds to get the response, you wouldn’t want your entire application to stop and wait for these two seconds. Instead, you would want to perform other tasks and deal with the response when it’s ready. This is where asynchronous JavaScript comes into play.

Top comments (2)

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Eckehard

Sorry, but your post is not very helpful. It provides less information than Wikipedia.

There is much to say about this topic, specially if you mention Javascript. I would kindly encourage you to provide some helpful information in your post so it get´s more value to the readers.

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anfal_ratul profile image
Anfal Ratul

Thank you for your feedback; next time, I will try to explain more in easy ways.