Check machine logins

Sometimes you want to know when someone logs in to your machine when they shouldn't or when you started working on your machine.

The quickest way on osx is a simple

last | grep reboot

It should return a list of your login times

reboot    ~                         Wed Dec  4 09:48
reboot    ~                         Tue Dec  3 08:18
reboot    ~                         Mon Dec  2 08:00
reboot    ~                         Sun Dec  1 08:52
reboot    ~                         Sat Nov 30 10:16
reboot    ~                         Fri Nov 29 18:04
reboot    ~                         Thu Nov 28 18:41

Which will tell you when your machine was accessed and also acts as a handy indicator of when you start work each day.