I am new to TFS, I have been mainly using Subversion. I am confused with the "mapping" concept. It looks like TFS maps a local folder to a source controlled folder. So every local change I make "automatically" gets added to source control??? 

I only ask b/c I am got the latest version of a project that was built using Visual Studio 2005, and I have Visual Studio 2010. So of course I have to convert it on my "local" folder, but the source folder already "sees" that I have made that change. I tried to undo pending changes, but the solution in source control still shows the VS2010 icon. Hopefully I did not change the solution for everyone else to VS2010 when I didn't even commit any changes.

Is there a way to back out any changes?