Checking your computer’s login times can be helpful. For example, if you’re wondering if someone—maybe a roommate or your child— has been using your computer without authorization, you can check to see if someone logged in and at what time it occurred. Or perhaps you just want to see how hard you’ve been pushing your Mac! h
To do this:
In the Finder, go to the “Go” menu
Click on “Applications”
Find the “Utilities” folder
Launch the application “Console”
You will see your activity on your computer. In the filter area (top right), enter “wake” to see login information. On the very left you will be able to see the time the computer was logged in to. You can compare those times to the times you know you were on the computer.