PC Hardware A Beginner’s Guide

(^448) PC Hardware: A Beginner’s Guide
 DELETE The function of this key is controlled by the software application
running on the PC, but it is essentially used to remove a single character to
the right of the cursor or a selected object.
 HOMEandEND In most applications, theHOMEkey positions the cursor at the
beginning of a text line. TheENDkey does the opposite and moves the cursor to
the end of a text line. When used in combination with other keys, such as the
CTRLkey, theHOMEkey moves the cursor to the beginning of a document, and
theENDkey moves the cursor to the end or bottom of a document.
 PAGE UPandPAGE DOWN These keys are used primarily in document-based
software to scroll one entire screen up or down. On many keyboards they are
labeledPG UPandPG DN.
The Number Pad
Every one of the keys on the number pad can be found elsewhere on the keyboard. This
set of keys, shown in Figure 18-7, was originally added to the keyboard to facilitate the
entry of numeric data. It replicates the key placement used on a ten-key calculator or
cardpunchmachine.Mostuserssimplyignoreit,butforthoseuserswhomustenterlarge
volumes of numeric data, the numeric keypad is an absolute necessity.
The keys included in the number pad are as follows:

NUM LOCK This key is used to toggle and lock the number keypad between
its function as a number pad and its cursor control function. The default setting
(on or off) for theNUM LOCKis set in the PC’s BIOS settings. Virtually all
systems set theNUM LOCKon during the boot and leave it on, ignoring the
cursor control functions of the number pad.
 Arithmetic operators The number pad includes keys for the four standard
arithmetic operators,/(divide),*(multiply),-(subtract), and+(add).
Figure 18-6. The cursor command and navigation keys on a standard keyboard