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Lære Comparing Synchronous and Asynchronous Code | Foundations of Asynchronous JavaScript
Asynchronous JavaScript Explained

bookComparing Synchronous and Asynchronous Code

When you compare synchronous and asynchronous approaches in JavaScript, their practical differences become clear. Consider the synchronous code sample from earlier: each line waits for the previous one to finish before running. If a task takes a long time—such as reading a large file or waiting for a network response—the entire program pauses at that point. This means your application can become unresponsive to users if a slow operation is in progress.

By contrast, the asynchronous code schedules time-consuming operations to run in the background. While those tasks are being handled, the rest of your code continues to execute. For example, if you request data from a server asynchronously, your program can keep responding to user input or perform other work while it waits for the data. The result is a smoother, more interactive experience for users, especially in web applications where delays can be noticeable.

Note
Note

Synchronous code blocks further execution until it completes, while asynchronous code schedules tasks to run later.

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Which scenario would benefit most from asynchronous code?

Select the correct answer

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Seksjon 1. Kapittel 3

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bookComparing Synchronous and Asynchronous Code

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When you compare synchronous and asynchronous approaches in JavaScript, their practical differences become clear. Consider the synchronous code sample from earlier: each line waits for the previous one to finish before running. If a task takes a long time—such as reading a large file or waiting for a network response—the entire program pauses at that point. This means your application can become unresponsive to users if a slow operation is in progress.

By contrast, the asynchronous code schedules time-consuming operations to run in the background. While those tasks are being handled, the rest of your code continues to execute. For example, if you request data from a server asynchronously, your program can keep responding to user input or perform other work while it waits for the data. The result is a smoother, more interactive experience for users, especially in web applications where delays can be noticeable.

Note
Note

Synchronous code blocks further execution until it completes, while asynchronous code schedules tasks to run later.

question mark

Which scenario would benefit most from asynchronous code?

Select the correct answer

Alt var klart?

Hvordan kan vi forbedre det?

Takk for tilbakemeldingene dine!

Seksjon 1. Kapittel 3
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