What is Parameter Random Access Memory (PRAM)?
System configurations are kept in PRAM, a form of memory used in Macintosh systems. These options include the time zone setting, audio level, starting loudness option, display options (such as screen size and color density). Although the system configurations kept in the PRAM of the computer vary from Mac to Mac, the memory's function is the same.
You may want to attempt refreshing the PRAM if your Macintosh is acting strangely or not starting up completely. By holding down the Command, Option, P, and R buttons as the computer turns on, you can "blast" or restart the PRAM on a Mac. You must press all four buttons at once, that much is true. The PRAM has been refreshed and you can drop the buttons once you hear the starting sound a second time.
Remember that if you choose to reduce your PRAM, you might need to use System Settings to change your display, time zone, starting level, and other impacted options. You may need to restore the impacted settings after the implementation of some software upgrades because they might reboot your PRAM during the installation procedure.