JavaScript

JavaScript is a general-purpose scripting language available in most Web browsers. It can be embedded within standard Web pages to create interactive documents. Each JavaScript interpreter supplies the needed objects to control the execution environment, and because of differences the functionality can vary considerably.

Within the context of a Web browser, the language is powerful, allowing prepared scripts to modify the Web page and perform calculations on the client side, improving perceived performance and potentially reducing the load on the server. Within a browser context, JavaScript does not have methods for directly accessing a client file system or for directly opening connections to other computers besides the host that provided the content source. Moreover, the browser normally confines a script’s execution to the page in which it was downloaded.