You can perform PureCM operations on a file by right-clicking the file in the Explorer and selecting the 'Team' menu.
'Check Out' will make the file writable, ready to start working on. After a file is checked out it will appear when you select 'Team | View My Changes' and will also appear when you submiit your changes.
'Check In' will create a local revision or checkpoint. This local revision will only be available in your workspace, it will not be shared to all developers. You must submit your changes to share them with other developers.
'Undo Checkout' will undo any changes you have made since your last checkin (checkpoint).
'Revert' will undo all changes since you started working on the file. So 'Revert' is the same as 'Undo Checkout' if you have not done a 'Check In'.
When you have finished your changes you need to submit them to the server as described in the section called “Submitting Changes”.