Does the Event Loop work the same in Node.js and in the browser?

The Event Loop in Node.js and browsers operates on a similar principle — it is a mechanism that allows processing asynchronous operations without blocking the main thread. However, there are important differences:

• Runtime environment: In browsers, the Event Loop manages handling of user interface events, network requests, timers, etc. In Node.js, the Event Loop additionally manages input/output operations, the file system, network sockets.

• Event Loop phases: In Node.js, the Event Loop is divided into several phases (timers, pending callbacks, idle, poll, check, close callbacks), each handling specific types of tasks. In browsers, the model is simpler and may differ in details.

• API and microtask queue: In browsers, microtasks (Promises, MutationObserver) are executed after the current macrotask, affecting the execution order. In Node.js, microtasks also exist, but their handling may differ.

Thus, the concept of the Event Loop is general, but its implementation and details depend on the environment. This is important to consider when porting code or understanding the behavior of asynchronous operations.