Visual Studio Command Prompt vs. a regular command prompt?

Question

When I open a Visual Studio command prompt (for example, opened with menu Start -> Programs -> Microsoft Visual Studio 2008 -> Visual Studio T

Answer 1

It basically just sets several of the Visual Studio binary locations into the PATH environment variable for that command window instance. This means you can use all the various commands and tools without having to include the full paths.

There's a partial list of some of the tools available on MSDN in .NET Framework Tools and Tools (.NET Framework).