User types in a command at a
character prompt and then the
operating system executes the
command.
Used in the early days of computing
Some of the commands may have 'switches' to provide options for the
command. E.g. in Microsoft operating systems, the command for listing the files
in a folder called 'DOCS' on drive C is DIR C:\DOCS
Some instructions may have a number of switches
and the commands could become quite complex
A switch, \W specifies that the
filenames are to be printed across
the screen instead of down and the
instruction that needs to be entered
at the command prompt is: DIR
C:\DOCS /W
Advantages
Instructions execute quickly
Instructions are versatile - meaning
the user can select a large number
of options for each intruction
The operating system is smaller when
loaded onto memory
Disadvantages
You need to learn the special intructions used
If you mistype a command or
misspell a word then it cannot be
executed
Some commands and their options can
be very complex, so high-levels of ICT are
needed