Firebug can be opened with a keystroke, have it as a bar at the bottom of Firefox or opened as a separate window. No matter how you decide to open it, Firebug makes it a breeze to edit HTML. Aside from its comprehensive HTML tools, Firebug also has several CSS tabs you can use for editing and checking web styles. Unlike other web development tools, Firebug lets you make changes and see the effect instantly, taking out the guesswork.
Firebug also makes it easy to position CSS boxes and line them, but that’s not all. One of the most common problems that web developers face is trying to figure out why web pages are taking too long to download. With Firebug you’ll have tools that will make it easy to check if you failed to compress images or there’s a problem with the script.