•  The top row of keys on your Apple keyboard can be used as regular function keys or as controllers for built-in Mac capabilities.
• Many distinct functionalities on your Mac are controlled by default by the top row of keys on your Apple keyboard. The volume can be adjusted by tapping the keys with speaker icons, for example.
• Depending on the app and the keyboard shortcuts you've put up, standard function keys work differently. Some apps have their own set of keyboard shortcuts that you can change.
• Hold the Function (Fn)/Globe key down while pressing a function key to use the normal function keys. For example, pressing both Fn and F12 (speaker icon) instead of raising the volume of your speakers accomplishes the action set to the F12 key.

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