Malware , short for malicious software, is software designed to
secretly access a computer system without the owner's informed consent.
The expression is a general term used by computer professionals to mean
a variety of forms of hostile, intrusive, or annoying software or
program code.
The best-known types of malware,
viruses and worms, are known for the manner in which they spread, rather
than any other particular behavior. The term computer virus is used for
a program that has infected some executable software and that causes
that when run, spread the virus to other executables. Viruses may also
contain a payload that performs other actions, often malicious. A worm,
on the other hand, is a program that actively transmits itself over a
network to infect other computers. It too may carry a payload.
These
definitions lead to the observation that a virus requires user
intervention to spread, whereas a worm spreads itself automatically.
Using this distinction, infections transmitted by email or Microsoft
Word documents, which rely on the recipient opening a file or email to
infect the system, would be classified as viruses rather than worms.
In
my experience, malware is one of the most common and annoying issues a
PC owner has to combat. Fortunately with a handful of free tools it’s
easy to keep malware in check. Here’s how I do it with free tools.