What is the event loop in Node.js?

Vaibhav Kothia May 26, 2023 0 Comments

The event loop in Node.js is a mechanism that allows asynchronous code to be executed. It works by allowing the execution of code to be delayed until an event occurs, such as a user input, a network request, or a timer expiring. The event loop is responsible for queuing up tasks and scheduling them to be executed in the correct order.

For example, when a user makes an HTTP request, the event loop will queue up the request and wait for a response from the server. Once the response is received, the event loop will execute the callback function associated with the request. This allows the user to continue interacting with the application while the server is processing the request.

What is the event loop in Node.js?

Vaibhav Kothia May 26, 2023 0 Comments

The event loop in Node.js is a continuous loop that is responsible for executing asynchronous callbacks when an event occurs. It is the mechanism that allows Node.js to perform non-blocking I/O operations — despite the single-threaded nature of JavaScript.

Example:

Let’s say you have a Node.js application that needs to read a file from the disk. Normally, this would be a blocking operation, meaning that the application would freeze until the file is read. However, with the event loop, the application can register a callback function that will be executed when the file has been read. This way, the application can continue to do other tasks while the file is being read, and when the file is finished reading, the callback will be executed.