The "last" command displays when users logged into your system, when there were reboots and shutdowns, the kernel that was booted... Example:
Code:
[root@li-20 root]# last
root pts/1 zon122191aaa.def Thu Jun 26 14:36 - 15:25 (00:49)
root pts/0 zon122191aaa.def Thu Jun 26 13:11 still logged in
root pts/0 zon122191aaa.def Thu Jun 26 00:48 - 05:50 (05:01)
root tty0 Tue Jun 24 16:59 still logged in
reboot system boot 2.4.21linode4-6u Tue Jun 24 16:58 (2+05:48)
wtmp begins Tue Jun 24 16:58:25 2003
[root@li-20 root]#
It also displays where the user came from and what they connected to - (console, ftp, a terminal, etc). "tty0" is the console, where as pts (pseudo terminal) was an SSH or telnet session.
-Chris