Page 110 - ICT_for_JHS_Classical

Chapter 16 - Threats to Computers

Computers are vulnerable to many threats. The main and most serious threat to
computers are viruses.

Computer Viruses

A computer virus is a program or a code that is loaded onto your computer

without your knowledge and against your wish. In fact, it is a malware when
executed, replicates by producing itself or infecting other programs by
modifying them. Viruses infect computer programs as well as data files and boot
sector of the hard drive.

All computer viruses are man-made. A simple virus can make copies of itself
over and over again. Even such a simple virus is dangerous because it will
quickly use all available memory and bring the system to a halt. An even more
dangerous virus is capable of transmitting itself across networks and by-passing
security systems.

No matter how careful you are, you can pick up computer viruses through
normal web activities.

Effects of computer viruses do
Some computer viruses are programmed to harm your computers by damaging
programs, deleting files or reformatting the hard drive. Others simply replicate

themselves or flood network traffic, making it impossible to perform any
Internet activity. Even less harmful viruses as said earlier, can significantly
disrupt your system performance, sapping computer memory and causing
crashes.

Symptoms and Effects of Viruses in a Computer

1. Slow computer performance
2. Computer not starting

3. Erratic computer behavior
4. Unexplained data loss
5. Frequent crashes
6. Unexplained memory used up
7. Pop up ads