Hot corners are corners of the screen that allow you to quickly initiate certain actions simply by moving your cursor into them. Although they aren’t activated on Macs by default, hot corners can easily be enabled and customized to suit your needs.
To set up hot corners on a Mac, open System Preferences and head to the Mission Control preference pane. Then, click the hot corners button in the bottom left corner of the window. Lastly, select one of the nine actions for any corner of the screen that you want to turn into a hot corner. These operations range from opening Mission Control to making your Mac’s screen sleep. Once you feel confident in your hot corner’s activity selections click “OK.” Now you can begin utilizing your newly enabled hot corners.