Epson Apex 20020, 20040 User Manual page 240

Relative pathname
A pathname that does not begin with the backslash character.
A relative pathname tells MS-DOS how to find its way to a
given directory, starting at the current default directory. See
also Absolute pathname.
Reset
To reload a computer's operating system so you can retry a task
or begin using a different operating system. Resetting erases all
information in RAM.
RGB
Red Green Blue. A type of color monitor.
ROM
Read Only Memory. A portion of memory that can only be
read and cannot be used for temporary storage. ROM retains its
contents even when you turn off the power.
Root directory
The top level directory in MS-DOS, designated by a \
(backslash). All other directories are subdirectories of the root
directory or of other subdirectories.
RS-232C
A widely-used, standard type of serial interface. You can easily
connect an RS-232C-compatible device to the computer.
Sector
A contiguous section of a disk track that provides an address at
which the computer can access data.
Self test
The initial diagnostics procedures a system performs to check
its hardware.