Very popular, the JavaScript programming language is mainly used for the design of many online tools. Developers use it to optimize the interactivity of a platform with add-ons such as games, animations, or forms. More than 90% of the sites that exist today use this language for the design of their various pages. If JavaScript remains in demand, it is because it is versatile, easy to master, and you have the possibility to deploy it on a computer as well as on a phone.