Building a modern interface
There are two parts to a web-based platform such as ServiceNow: the central server, which is where most of the data is stored, and the client browsers that ask for the data, display it, and then push information back to the server.
ServiceNow takes advantage of modern web browsers to provide a simple-to-use and feature-rich interface. This is built with JavaScript, the language of the Web. JavaScript is very capable, giving you control over the whole interaction with the user.
Note
Most ServiceNow system administrators have had some experience working with client-side JavaScript. So, writing scripts that interact with a web browser is often simple and familiar. The fact that ServiceNow also uses JavaScript on the server is a bonus: you only need to know one language.
The power and pitfalls of Ajax
Modern websites make heavy use of asynchronous JavaScript and XML (Ajax), a technique built by Microsoft but popularized by Google. It is the key method for loading data...