Read/write head

The physical device inside a disk or tape drive that reads data from and writes data to the magnetic surface of the disk or tape.

Real-time clock

A clock inside the computer that keeps track of the time and date, even when the computer is turned off, by using power from a backup battery.

Refresh rate

The frequency with which a monitor can redraw a screen image. The faster the refresh rate, the less the screen will flicker.

Reset

To restart a computer without turnin it off. You can reset your computer by pressing (ctrl)0000(71 . Resetting erases all data stored in RAM and reloads your operating system.

ROM

Read Only Memory. A portion of memory that can only be read and cannot be modified. ROM retains its contents even when you turn off the computer by using power from a backup battery.

Root directory

The highest or main directory in a hierarchical disk directory structure. All other directories are subdirectories of the root directory. MS-DOS designates the root directory with a \ (backslash).

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