When your nosey coworkers enjoy peeking on other people’s desktops when they are gone, or you simply don’t want your kids to accidentally erase your soon-to-be-complete Pulitzer story while you were in the kitchen, your mac has the quick and simple solution, one that few people know exists: the screen lock
Enabling screen locking is pretty easy, although hidden where you’d least expected it. Here’s how it’s done:
You’ll need to open up Keychain Access, a utility app that comes preinstalled on your Mac and can be found inside the /Applications/Utilities/ folder. Once there, you’ll open up the Preferences menu (press ⌘, or as the submenu of Keychain Access menu). In the General tab, make sure the checkbox ‘Show Status in Menu Bar’ is checked. A tiny lock icon will appear in the menu, somewhere on the right. Clicking on it will reveal the long awaited option: Lock Screen.
PS. Make sure you know your mac password before clicking on it, because only those who know it will be able to unlock the computer.