Question

define virus . Plz answer fast ..

Answer 1

HELLO THERE!!

There can be two probable definitions of Virus:

1. According to Biology,
A virus is a infectious agent of small size and simple composition that can multiply only in living cells of animals, plants, or bacteria. A virus itself is non-living. The term virus is derived from the 'Latin' term, which means 'poison'. 

Virus can cause many infectious diseases. Some viral diseases are Measles, Smallpox, Chicken pox, and so on.These diseases can be prevented by vaccination. Vaccination is the process in which the dead or weakened germs is introduced in our body, so that antibodies are developed and immunity is provided to us against that specific disease.



2. According to Computer Science,
A virus is a malicious software/program which infects the computer/smartphone device and can steal many information of the user and make it public. Now a days, there are viruses which can even affect Android smartphones. They steal many information such as Contacts, WhatsApp contacts, and so on.

Some well known viruses are:
1. Trojan Horse
2. CIH (The Chernobyl virus)
3. The Anna Kournikova worm
4. ILOVEYOU
5. The Melissa virus
6. The Blaster Worm
7. Netsky and Sasser
8. OSX/RSPlug
9. Storm worm.

These are the worst computer viruses as specified by the Telegraph.
Your computer/smartphone can be secured if antivirus softwares are installed and activated. 

[Note: Some smartphone antivirus software, that are available in Google Play are fake; they do not actually scan for viruses, but warn you if there is no app lock, no intruder-selfie activation. Most of them are just cleaning apps, which advise you to clean the RAM all the time. However, the paid version of Kaspersky is trusted!!]

HOPE MY ANSWER IS SATISFACTORY...
THANKS!

Answer 2

according to biology viruses are infection causing microorganism which uses human DNA and multiply their number.they infect our immune system.
viruses are called borderline between living and nonliving as they exhibit the characteristics of both living organism and non living thing.they are floating in air or settled on a door knob they are non living like sugar and salt but when they come in contact with a suitable plant ,animal or bacteria they show the characteristic of living organism they infect the cell quickly and multiply their number.

hope it help you