A Computer virus is malicious software designed with the purpose of damaging a file or system. Computer viruses possess many modes of spreading and are capable of self-replication. Viruses can spread either through simple file-sharing programs to email attachments and even instant messages.
Computer virus types
- Worms: These types of viruses are self-replicating and can spread through networks, damaging several files and systems.
- Ransomware: This virus can hijack a device, after which it will encrypt every file contained in it. The attacker will release the device and its files only after a ransom is paid.
- Adware: This kind of virus isn’t altogether malicious, but it is still a source of inconvenience, displaying intrusive and constant ads.
- Spyware: Spyware, as the name suggests, once inside your system, spies on your private traffic and activities and relays it back to the attacker.
- Trojan: A trojan is a kind of virus designed to pose as a legitimate program.
- Macro viruses: A kind of virus that is primarily attached to documents and is only activated when the user opens the document.
History of computer viruses
- Creeper system: BBN Technologies created this virus in 1971. It was designed to make copies of itself until the device’s hard drive was full.
- Brain: Tagged as the first MS-DOS virus, Brain was created in 1986 and would disable the computer’s booting function upon infection.
- CIH: Famously known as the Chornobyl and Spacefiller, the virus was designed to damage Windows computers by overwriting key system files.
- Melissa: A virus designed to attach itself to an MS Word document.
- WannaCry: Arguably the world’s most harmful and recurrent ransomware viruses.
