About "Sleep" and "Deep Sleep"
"Sleep" and "deep sleep" are used to refer to low-power modes of the computer.
When you select the Sleep command in Mac OS (or when the computer goes to sleep as a result of Energy Saver settings), as many components as possible will enter a low-power mode.
If all hardware components and connected peripherals are in a low-power mode, your computer is in "deep sleep". However, not all hardware components and peripherals are capable of running in a low-power mode.
If one or more hardware components or peripherals does not enter a low-power mode, your computer may simply sleep.
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