Javascript is an excellent and universally supported scripting language. This is one of the reasons that it's suitable for creating applications such as games for web pages. There's no need for any third party software to be installed before the game can be run. It does not need to be downloaded and installed. All that's needed is a web browser. Any web browser. And the programmer does not need a high-tech, memory intensive integrated design environment (or IDE). They just require a simple text editor.
The other great thing about Javascript is that it is a full blown object oriented programming language. A programmer can create a complicated class (such as a game character to be animated) complete with its own custom properties and methods.
Setting up the Javascript Programming Environment
The programmer starts with a text editor and some simple HTML: