You will need the Permissions Limited permission to perform this action.
Whenever someone attempts to log into the system, the outcome is logged and viewable within the system. All logs can be viewed by going to the cog menu in the top header and then going to Security > Login Logs.
The log will not only show whether the attempt was successful or not, but it also shows the IP address and geographical location (based on IP) of the user.
This can also be viewed on a person's profile as well by clicking on "view history" at the bottom of the right most column.