JavaScript is a language that's used by more than 64% of developers, according to the State of JavaScript 2019 survey. It is also used to build web applications and server-side applications. The advantage of using JavaScript is that it allows you to develop a whole application without being tied to one language or framework, as you can use the same language on the front-end and back-end sides.
JavaScript testing frameworks help us to check the correctness of our code. They can also execute automated test cases on various browsers or mobile devices. Top 7 Best JavaScript Open Source Testing Libraries: react-fix-it - Automagically generate tests from errors; testcheck-js - Generative testing for JavaScript; redux-test-recorder - redux middleware to automatically generate tests.