Baddies
Along with all the nice programs that run on our computers helping us with our work and play, every now and then we’re going to face some nasty bits of code that can irritate or wreak havoc on our machines.
So, let’s have a look at what’s going on.
Viruses
Most people have heard of computer viruses, but what are they, and where do they come from, and what can you do about them?
They are just little bits of code that when they get on your computer ‘infect’ the programs on your computer and do anything from sending you annoying little red monsters to erasing all your files. They are called viruses because like human viruses they replicate themselves and spread from program to program, and spread from computer to computer by email or when you download or copy files from infected machines.
Where do they come from? Well, programmers write them. Because they can. Some cynics also suggest that sellers of anti-virus software may also contribute to the pool of viruses.
Spyware
Spyware is a bloody nuisance at its least harmful, and bloody harmful at its worst. In the former caseit will send back information to its originator of your browsing habits; for instance, if you subscribe to an online magazine, or use an online store, they may put a bit of tracking software, or spyware, to see what other magazines or stores you visit for their market research purposes.
At its worst spyware will search your files for passwords, credit card numbers, or bank account details.
Trojans
Trojans are nasty bits of spyware that get on your computer by masquerading as something else. So when you download your ‘Free Smilies’ or run that ‘Free Spyware Scan’, you can often be giving permission for a trojan program to be installed on your machine.
No such thing as a free lunch!
Worms
A worm is a self-replicating computer program similar to a computer virus. Whereas a virus attaches itself to, and becomes part of, another program, a worm is self-contained and does not need to be part of another program to propagate itself. A worm uses a network to send copies of itself to other computers and it does so without any intervention. Once on your computer it can do similar damage to your files as a virus.
