sleep mode

Sleep mode (or suspend to RAM or stand by) is a low-power mode for electronic devices such as computers, televisions, and remote controlled devices. Sleep modes save significantly on electrical consumption compared to leaving a device fully on and, upon resuming to a working state, allow the user to avoid having to reissue instructions or wait for a machine to boot.
Many devices signify this power mode with a pulsed or red-colored LED power light.

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