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(a) What is a Computer virus?
(b) How can we protect our data from viruses?
(c) Why is it necessary to backup data regularly?
(d) What is meant by Copyright? Explain.

(a) Computer Virus
A program or piece of code that can infect the computer system and files stored in it Computer virus. It can load into the user’s computer primary or secondary memory without user’s knowledge. It can also replicate itself and can make many copies in the memory or on the disk. The code for a computer virus is written in programming language. A file containing virus is called infected file.

(b) We can protect our data from viruses by using following ways:

• Install latest anti-virus program on the computer and update these antivirus programs periodically.
• We should minimize the data transfer between computers through the use of removable storage media such as USB flash drives, CDs etc.
• Do not download freeware and shareware program from internet without checking it for viruses.
• Never open e-mail received from unknown address.

(c) A duplicate copy of the data taken on secondary storage is called backup of data. It is very important to take the backup of data regularly. The important data stored on the system may be lost or deleted or corrupted due to any reason. The backup of data can be used to recover the deleted data or corrupted data.

(d) Copyright is the branch of law. It protects the creative work from illegal use by other people. The creative work remains the property of the creator or owner. The owner holds all rights. No one allowed to use his/her creative work illegally. Copyright protects the rights of creators and ensures that they will get their money back. The creative work is sold to be used by only those who purchase them. This condition is imposed by the copyright.