has got to be my favorite JavaScript library! Just FTP a few files to your web server and included them with a couple <script> tags. You won’t notice anything different at first, but your site has just become dynamic. With an insanely small amount of code you can create cool JavaScript effects, sortable elements, easy AJAX queries, AJAX autocomplete forms, and more. It’s based off the Prototype Framework, and anyone can use it for free. And I really do mean anyone! Just take a look at their quick Getting Started Guide and you’ll see. You can for a really basic example have a DIV disappear with a cool animated effect when it’s clicked just with this code:

<div onclick=”new Effect.SwitchOff(this)”>
Click here to close this DIV!

It’s amazing what you can do. AJAX queries become so easy you don’t have to think about it, complex drag-and-drop scripts become a few lines. If you’ve used JavaScript before, you can do it. Try it out.