On Unobtrusive JavaScript

Traditionally, unobtrusive JavaScript means the code is kept separate from the page's markup. This separation makes it easier to maintain and reuse the code. However, I view unobtrusive code as more than simple separation. True unobtrusiveness means your JavaScript code will function alongside other code that may be loaded by the browser, and the other code will function alongside yours. Don't pollute the global scope in the execution environment; don't clobber global objects, their properties, or prototypes with your own; and be able to work alongside various frameworks.