I am using Visual Studio 2012 with TFS. Whenever I want to compare my checked out files, I have two options to choose from:
What is the difference ?
Comparing with workspace version actually compares the edited file with the version of file at the time you checked out (compares exclusively your changes).
Comparing with latest version compares the edited file with latest version of file present at your code repository i.e. it might include changes made by your colleagues.
http://codereferences.blogspot.ca/2012/03/tfs-compare-with-workspace-version.html