Use hot corners on Mac
You can use the corners of the screen as hot corners, to quickly start actions when you move the pointer to a corner. For example, you can start the screen saver when you move the pointer to the top-left corner of the screen, or lock the screen when you move the pointer to the top-right corner.
Tip: By default, the bottom-right hot corner is set to Quick Note, so you can quickly open a note to jot down your thoughts at any time. See Start a Quick Note.
On your Mac, choose Apple menu
in the sidebar. (You may need to scroll down.)Click Hot Corners on the right.
For each corner you want to use, click the pop-up menu, then choose an option, such as Notification Centre, Launchpad or Lock Screen.
To use a modifier key with the hot corner, press and hold the Command, Shift, Option or Control key or a combination of these keys, while viewing the pop-up menus.
Click Done.
