At the Forge - Firebug
which, on the Linux Journal home page, produces the following form header:
<form id="cvb_form" action="/" method="get">
Clicking on the code allows you to set a breakpoint (including a conditional breakpoint) to copy the function (useful when trying to communicate with other programmers or even when writing a column about programming) or to handle a breakpoint by continuing or stepping through the code.
Finally, the Net button makes it easy to keep track of any Ajax calls embedded in the page. Clicking on Net and XHR produces a graphical indication of the Ajax calls that have been made on this page, as well as how long each took to execute. If you are developing an Ajax application, this is the best way to find out where your bottlenecks are.
It's rare for me to call a product revolutionary, but I am sorely tempted to do so in the case of Firebug. It puts a lot of information in one nicely designed, easy-to-use package. The ability to interact with my packages has a vaguely Lisp-like feel, in that I'm suddenly interacting with a live environment. Firebug has given me the ability to “see” what my pages are doing and to better understand them.
Firebug has become an indispensable tool in my arsenal, alongside the Web Developer extension. In this way, Firefox is beginning to demonstrate that it is indeed a platform for Internet applications, rather than merely a Web browser.
Reuven M. Lerner, a longtime Web/database consultant, is a PhD candidate in Learning Sciences at Northwestern University in Evanston, Illinois. He currently lives with his wife and three children in Skokie, Illinois. You can read his Weblog at altneuland.lerner.co.il.