Summary of useful CVS commands

Command Description
cvs add  dir adds directory  dir
cvs add  file1 ... filen adds text files file1 ... filen
cvs add -kb  file1 ... filen adds non-text (e.g. code, gif, jpeg etc) files   file1 ... filen
rm  file; cvs rm  file deletes and then removes  file (alternatively use cvs rm   -f   file)
cvs rm   -Rf   dir recursively deletes and removes all files in  dir (N.B. can't delete directories, but see cvs update -P below)
cvs ci check-in all files reachable from current directory and invoke $EDITOR for message
cvs ci  file check-in file  file and invoke $EDITOR for message (N.B. can't check-in named directories)
cvs {-q} update {-P} {-d} updates current directory tree from CVS repository
{ } surrounds optional items, "-q" for quiet, "-P" prunes empty directories, "-d" gets new directories
if you get a file with junk like <<<<<< in it, then try deleting the local copy and doing another update

For more details see Open Source Development with CVS (a free CVS book by Karl Fogel) and the shorter CVS-RCS-HOWTO.