#! code

JS Bin is an online tool that allows you to test JavaScript without having to muck about with files. You can just quickly cut and paste some code in and view the output. It is even possible to make the code you are looking at public and then use this as part of an ajax call in another instance of the application.

To get you started there is a nice help section, which also includes a couple of videos.

This tool really impressed me, especially the easy inclusion of several different JavaScript frameworks. I don't mind testing JavaScript, but sometimes I just want to run a little bit of code on it's own to see why it isn't working as I expected it would. This tool fills that much needed gap, and the addition of allowing other people to view your code is a very nice feature. Well worth a look!

Written by Philip Norton.

Firebug is by far the best JavaScript debugging plug-in available for Firefox. I have been stuck on a few problems in the past and Firebug has usually provided me with a reason as to why things are going wrong. In fact when developing for other browsers (like Internet Explorer) I can feel a little blind as there are no debugging tools with the power and features of Firebug. It can allow you to stop JavaScript execution at any time using breakpoints.

Firebug is important if you are creating AJAX applications as it will tell you about every client/server communication, what headers where sent and what the response was.

Aside from the decent JavaScript features there are also a host of HTML and CSS features that allow you to edit styling code on the page in real-time or inspect a portion of the page for HTML and style information.

The only thing wrong with the program is that it can slow down some sites like Gmail, but you can turn it off for any site you wish. If you haven't tried Firebug I suggest that you give it a go.

Written by Philip Norton.