How to add a user in linux without using useradd command. Hint it makes use of passwd, group and shadow file.
Commands
edit /etc/passwd
techtuxedo555:x:999:999:This is without useradd:/home/techtuxedo555:/bin/bash
edit /etc/group
techtuxedo555:x:999:
chown techtuxedo555 /home/techtuxedo555
chgrp techtuxedo555 /home/techtuxedo555
and the user is ready for use.