For example, eventhough applets runon the client,they cannot
read or write data onto the client's machine. Additionally, ap-
plets are further restricted so that they can only read and write
data from the same domain that they are served from.
Macro virus A type ofcomputer virus thatis encoded asa macro embedded
in a document. Many applications, such as Microsoft Word
and Excel, support powerful macro languages.
These applicationsallow youto embeda macro ina document,
and havethe macro executeeach time thedocument isopened.
Mail client An e-mail client is an application that enables you to send and
receive e-mail.
Memory Internal storage areas in the computer. The term memory
identifies data storage that comes in the form of chips, and the
word storage is used for memory that exists on tapes or disks.
Every computer comes with a certain amount of physical
memory, usually referred to as main memory or RAM.
Non-heuristic This method of scanning relies on specific virus signatures.
The advantage of the non-heuristic scan is that it is not fooled
by what might seem to be a virus, and does not generate false
alarms.
Packed programs A file in a compression format. Many operating systems and
applications contain commands that enable you to pack a file
so that ittakes up lessmemory. Forexample, suppose you have
a text file containing ten consecutive space characters. Nor-
mally, this would require ten bytes of storage.
However, a program that packs files would replace the space
characters by a special space-series character followed by the
number of spaces being replaced. In this case, the ten spaces
would require only two bytes. This is just one packing tech-
nique - there are many more.
Path The exact directions to a file on a computer. These directions
are usuallydescribed by means ofthe hierarchical filingsystem
from the top down.
The routebetween any twopoints, such asthe communications
channel between two computers.
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