Extract the latest revision of the file and create a new working copy
Extract any previous revision which exists
Lock the file and extract a writeable copy for editing. Other users
will be able to check out read-only copies, but not modify or check in
new versions until the lock is released
Some of the frequently used options:
-l
Lock -- the working file is checked out writeable, and a lock is placed in the RCS file.
-rrev
Check out the specified rev instead of taking the default highest revision number.
-nName
Check out the revision named by the symbolic Name
-ddate
Check out the revision whose checkin date/time is less than or equal to date.
The date can be given in a very flexible format.