There are many frameworks to make working with web pages (via JavaScript) easier. All of them work cross browser, do events (window load, element click etc) and basic manipulation (get element, modify css, hide/show/move), but some do more than others. Syntax often differs between them. Choosing one to work with depends on what you want to do, and how much code you are willing to write yourself (sometimes it is more satisfying to figure out a solution to a problem yourself, rather than to rely on someone else's code). Like with any code, the more it does, the bigger the download for the client. So it may be best to go with the most minimal solution (no extra features you won't use). Here is a basic overview of what is available (that I know of) Prototype http://prototype.conio.net/ There is a useful reference for this at Prototype Dissected . As you can see from it, Prototype has quite a lot of features. Very widely used and quite a reasonably big file (approx 46kb). There...