To record a gameplay video use the command in console \record
U also can name the file > \record file1
after this u can stop the record using \stoprecord
to see your videos demonstration, just type \demo file1
* This commands is usefull to cathing hackers and cheaters, u record and send the demos to the admin of the server, its also usefull to make Gameplay videos. I usually use Fraps to edit my demos.