The fields in the passwd file are separated by colons and contain the following information:
username:password:UID:GID:comment:home-directory:login-shell
For example:
kryten:x:101:100:Kryten Series 4000 Mechanoid:/export/home/kryten:/bin/csh
For a complete description of the fields in the passwd file, see the passwd (1) man page.