is programming language, which is built on top of `JavaScript`. CoffeeScript compiles into JavaScript that is efficient and consistent with many best practices. And it offers a clean syntax that should appeal to anyone who likes `Python` or `Ruby`.
Actually, The CoffeeScript is just a JavaScript. So you can use any exsiting JavaScript library seamlessly from CoffeeScript. And both client-side and server-side can be written by CoffeeScript. So CoffeeScript can write entire web application completely, not like JavaScript only write client-side.