Undo – This option undoes a selected change and checks-in a new revision. This option opens the File Merging dialog where eventual conflicts must be resolved for each file separately. For information about how to merge files, refer to File Merging List in the Branching and Merging section.
Note: For binary files, only changes which are one revision below the head revision may be undone.
Redo – You may redo changes at any time, however, do not delay this action as merge conflicts may complicate this operation.