If you share your computer and you need to monitor who logs in and when, then you will really like the built-in Logon Auditing feature of Windows. By enabling this feature you will be able to check the accounts that log in your computer along with a timestamp. Furthermore, since you will be using the Event Viewer, you will be able to set up tasks whenever a user logs in your computer.
First you will need to enable the Logon Auditing feature. Press the Windows key, search for “gpedit.msc” and click on the result that appears. This will bring up the Local Group Policy Editor. Using the left side panel, navigate to “Local Computer Policy> Computer Configuration> Windows Settings> Security Settings> Local Policies> Audit Policy. Once you have clicked on that last time, you will see a list appearing on the right hand panel. Double click on the “Audit logon events” policy item to open a new window. Now, enabling the “Success” option will only monitor successful logins. Otherwise, check the other box too if you want to monitor all the attempts.
Now, every login will be logged in the Event Viewer. Open that utility by searching for it in the search box of the Start menu. Navigate to Windows Logs> Security. Then, search for event IDs 4624. These represent the successful login attempts. If you double click on the events, you will be able to see the name of the user that logged in and the exact time that he did. Now you not only have the information readily available, but you can also set tasks to trigger when this happens using the Task Scheduler.