JavaScript Execution: Call Stack & Event Loop

Let’s go over some important and commonly tested concepts of JavaScript during interviews. This includes the working of the call stack, web API, and event queue.

setTimeout #

JavaScript is single-threaded, meaning it can only run one command at a time. Due to this, commands are not run in parallel. Because the execution happens line-by-line, each command is considered synchronous hence blocking.

So, is it possible to run an asynchronous code in JavaScript?

This is where the setTimeout function comes into play. It is a web API provided by the browser that takes a callback function as its first parameter and time in milliseconds as its second parameter. It executes the callback function after the specified ...