Is javascript blocking or non-blocking?

JavaScript is a non-blocking programming language, which means it can handle multiple tasks without blocking or interfering with other tasks in the application. Unlike blocking programming, non-blocking programming can improve the performance of the program and is very efficient in processing input or output.

Blocking programming means that before a task is completed, the program will wait for its completion before proceeding to the next task. This can lead to poor performance of your application and introduce delays and slow response times when processing large amounts of data. In contrast, non-blocking programming uses asynchronous operations provided in the JavaScript runtime environment to achieve multitasking. Asynchronous operations allow tasks to be executed in a non-blocking manner. Even if one task takes longer to complete than others, the program can continue executing other tasks to improve application responsiveness and performance.

For example, when a program needs to obtain a large amount of data from a database, using blocking programming will cause the program to wait for the query to complete and prevent the execution of other tasks, resulting in delays. However, in non-blocking programming, the program can perform other tasks at the same time and continue to run other code in the application while executing the query.

In order to achieve non-blocking programming, JavaScript uses callback functions and Promise technology. The callback function means that after the asynchronous operation is completed, a piece of code will be executed in the program as a callback function. Promise is a more advanced asynchronous programming technology that makes the code more readable and maintainable, and can better handle exceptions.

It should be noted that although JavaScript is a non-blocking programming language, typing blocking code will still block the entire application.

In short, JavaScript is a non-blocking programming language that allows the program to perform multiple tasks at the same time, improving program performance and responsiveness. Through callback functions and Promise technology, JavaScript can perform tasks in applications in a non-blocking manner, process large amounts of data, and ensure that application responses are fast and smooth.

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