Page 118 - Viva ICSE Computer Studies 6 : E-book

Let’s learn about some threats related to the Internet.
Viruses

A computer virus is a program or a set of
programs designed specially to aff ect the normal
functioning of a computer. It is created by a
programmer to harm memory, processing speed,
essential data and programs of a computer
system. It can copy itself, attach itself to other
applications or fi les and infect a computer. It can
enter the computer through an infected fl oppy,
CD, pen drive or the Internet. It is usually intended
to aff ect a computer adversely without the user’s
knowledge. Computer viruses fi nd and attach themselves to an item in the computer system
such as the start-up memory area or an executable fi le. Most viruses stay active in the computer
memory until the computer is turned off .

A computer virus performs the following actions.
• It can infect the executable program fi les like Microsoft Word and operating system
programs.
• It can infect the fi le before it is attached to an e-mail message or transferred to a disk.
Thus, the virus spreads from one computer to another.

Spyware

Spyware is a software that is installed in a
computer or any other device without the user’s
knowledge and is designed to collect information
from the device. The information is collected in
the form of passwords, PINs, credit card and debit
card numbers, and is further processed to a third
party. The spyware also traces the browsing habits
of the user. It also aff ects the network system and
slows down the device in use.

Spamming

Spamming refers to the use of electronic
messaging systems like e-mails to send unwanted
messages to a large number of recipients. These
spams may include viruses, worms and spyware.
Spam e-mails are also received in the form of
offi cial letters from the banks or online payment
processors. The users should not respond to spam
e-mails and avoid opening such e-mails.

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