BIO
VIRUS A virus is a submicroscopic parasitic particle that infects cells in biological organisms. The study of
viruses is virology.
Viruses are obligate intracellular parasites that lack the cellular machinery for self-reproduction. Viruses infect eukaryotes and prokaryotes such as bacteria; viruses infecting prokaryotes are also known as bacteriophages or phages. Typically viruses carry a small amount of genetic material, either in the form of DNA or RNA, but not both, surrounded by some form of protective coat consisting of
proteins, lipids, glycoproteins or a combination. The
viral genome codes for the proteins that constitute this protective coat, as well as for those proteins required for viral reproduction that are not provided by the host cell.
Viruses are non-living particles that can only replicate when an organism reproduces the viral RNA or DNA. Viruses are considered non-living by the majority of virologists because they do not meet all the criteria of the generally accepted definition of life. Among other factors, viruses do not move or metabolize on their own. However, a comprehensive definition of life is still somewhat elusive since some bacteria (considered living) like rickettsia exhibit both characteristics of living and non-living particles.
COMPUTER VIRUS
In computer security technology, a virus is a self-replicating/self-reproducing-automation program that spreads by inserting copies of itself into other executable code or documents. A computer virus behaves in a way similar to a biological virus, which spreads by inserting itself into living cells. Extending the analogy, the insertion of a virus into the program is termed as an "infection", and the infected file (or executable code that is not part of a file) is called a "host". Viruses are one of the several types of malicious software or
malware. In a common parlance, the term virus is often extended to refer to
worms, trojan horses and other sorts of malware; however, this can confuse computer users, since viruses in the narrow sense of the word are less common than they used to be, compared to other forms of malware. This confusion can have serious consequences, because it may lead to a focus on preventing one genre of malware over another, potentially leaving computers vulnerable to future damage. However, a basic rule is that computer viruses cannot directly damage hardware, but only software.
While viruses can be intentionally destructive (for example, by destroying data), many other viruses are fairly benign or merely annoying. Some viruses have a delayed payload, which is sometimes called a
bomb. For example, a virus might display a message on a specific day or wait until it has infected a certain number of hosts. A time bomb occurs during a particular date or time, and a logic bomb occurs when the user of a computer takes an action that triggers the bomb. However, the predominant negative effect of viruses is their uncontrolled self-reproduction, which wastes or overwhelms computer resources.
Today (as of 2005), viruses are somewhat less common than network-borne worms, due to the popularity of the Internet. Anti-virus software, originally designed to protect computers from viruses, has in turn expanded to cover worms and other threats such as spyware.
More abstracts about the Bio Virus Vs Comp Virus - Analogous