Internet Explorer 8 Developer Tools
Windows Internet Explorer 8 includes the Developer Tools feature. This feature enables you to debug Microsoft JScript quickly, investigate a Windows Internet Explorer-specific behavior, or iterate rapidly to prototype or test a new design solution.
The following sections describe the important characteristics of the Developer Tools in Internet Explorer 8.
The Developer Tools are included with every installation of Internet Explorer 8, so you can debug issues on any computer that is running Internet Explorer 8. In addition, the tools load only when you need them to limit how they impact the browser's performance. By using the Developer Tools, you can rapidly debug only the current Internet Explorer process, instead of debugging for all of Internet Explorer.
Instead of reverse engineering how your website works or modifying your site to output debug information, the Developer Tools let you look into Internet Explorer to view its representation of your site. This view reduces the time that you spend debugging dynamic sites, where source inspection is not useful, or investigating an Internet Explorer-specific behavior, where a generic authoring tool cannot help.
When you are prototyping a new design or testing fixes in previous versions of Internet Explorer, you likely edit your source, save it, refresh your page in the browser, and repeat. The Developer Tools streamline this scenario by enabling you to edit your site within the browser and see changes immediately.
To access the Developer Tools, press F12 while you are viewing a webpage or click Developer Tools on the Tools menu.