Difference Between Virus And Bug
Malicious viruses are used for illicit commercial purposes, such as delivering bulk e-mail (“spam”) anonymously. Viruses that cause Distributed Denial of Service (DDoS) attacks are clearly intended to cause economic harm. These viruses flood a Web server with meaningless requests in the hope of shutting it down.
Viruses can be efficiently transmitted via e-mail. This method takes advantage of the ability of modern mail-reader programs to automatically open and execute programs attached to messages. The virus can spread very rapidly by mailing a copy of itself to other people on the recipient’s address list. A “Trojan horse” virus is a program that appears harmless but hides its true agenda. Trojan-horse viruses commonly are used to allow the hacker to open “back doors” in a system and operate as the system’s administrator. Some viruses are known as “worms.” Worms cannot attach themselves to other files as viruses can. They are able to propagate themselves without first being attached to another file. For example, a version of the Storm Worm in 2007 was a type of Trojan-horse program. For several weeks the worm was sent in e-mails that appeared to link to a news article about a natural catastrophe. (An estimated 200 million such e-mails were distributed worldwide.) But actually, clicking the link initiated a download of the worm to the victim’s computer. The computer then became vulnerable to remote control by the hacker behind the attack.
A bug is an error in computer hardware or software that prevents it from functioning properly. According to computer folklore, the original bug—though certainly not the first computer error—was a moth that short-circuited a connection in a 1940s machine being used by Grace Murray Hopper, the mathematician who spearheaded the development of the computer language COBOL. Removing the moth cleared up the problem. Hopper taped the moth into a logbook and next to it wrote, “First actual case of bug being found.” The process of locating and correcting bugs is called “debugging” and is standard procedure in the computer industry. Special software programs—”debuggers”—help programmers locate and eliminate these errors. Bugs, which are inadvertent malfunctions, are different from computer viruses.