Cursor; Ms-Doscommands - Epson CW3S16 Operation Manual

This is the system prompt. When it is displayed, it means
that MS-DOS is waiting for you to tell it what to do. This is
done by typing a DOS command, then pressing the ENTER
key.

Cursor

Following the system prompt, you will see a blinking underline
( _ ) character.
This is the "cursor". The cursor shows you where the next
character you type will appear on the screen. As you can see
here, any command you type will appear immediately to the
right of the system prompt and on the same line. Application
software often uses the cursor as well, allowing you to use the
cursor control keys to move the cursor around on the screen.
MS-DOS Commands
DOS commands instruct your computer to perform tasks such
as display a disk directory, copy a file, delete a program, etc.
These are called internal commands and can be used anytime
after the system has loaded MS-DOS into memory. They do
not require the MS-DOS main system diskette to function.
More complex DOS commands are actually separate programs
that provide powerful features for your computer. These are
called external commands, and perform such tasks as
formatting a diskette, comparing files on different disks,
backing up a hard disk, etc. These commands require one or
more of the MS-DOS diskettes.
Hard disk system user's can run any DOS command without
diskettes because the programs are stored on the hard disk
drive,
Using MS-DOS With Your Computer
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