What are they?

Computer viruses are pieces of software disguised in another file that infects or installs itself into a computer to harm it in any way.It may attach other files
too and so can spread and cause havoc.

There are also other types of viruses:

MalWare is actually short for Malicious Software. It is software that intends to harm a computer, damage a computer and also disable computer systems.
Malicious Software has these types in their category:
  • Computer viruses
  • Trojans
  • Worms
  • Root kits
  • Spyware
  • Adware



Trojans are a type of malicious software that hides in another file as well. It may appear to be useful software, but then can harm your computer once it
is installed or run. People that receive the trojan expect it to be something else.

How do they get on your machine?

Trojans may come into your system as an email attachment, as a file via your instant-messaging application, or even through file-sharing software.
It could be a photo, music, a video or even a game that you may download, disguised.
You may just have installed something quite nasty on your computer, and chances are that there will be a trojan Trojan that will make sure it runs every time you start your computer. This means you have created a back door for someone to your computer.

Things that Trojans may do to your computer

Some of them may be relatively harmless to your computer.
Some of them may take years until the Trojans are accessed and may open up the possibility of someone accessing your PC.
It can all depend. Other Trojans pose a far greater threat to your computer. They could even monitor your internet connection when active and steal
your information like your email or bank account details. Once they are finished however, they may leave the door open to others so they can access
your information.
You don’t want it there, and you need to protect your system from this happening.

Ways of protecting yourself from a Trojan

The best way to protect your computer from contracting a trojan virus is to be running a bulletproof kind of antivirus software. This will help a lot. Other ways can help like only downloading form a trusted source as Trojans disguise themselves as another program.


Spyware is a type of Malware.
It is Any software that gathers user information through the user's internet connection without him or her knowing about it. It is mainly used by people for advertising purposes.
Here are some images to illustrate spyware:
This is a picture to show what it will be like if some Spyware would go into a PC users internet

Spyware monitors the users activity on the Internet and transmits the information that is given in the background to the,. Spyware can also gather information about email addresses, user accounts, passwords and even credit card numbers!

How do they get on your machine?

Spyware applications are actually in a bundle with another file, but they are a hidden component, so they work similar to a Trojan. It is also similar to

the Trojan horse in that users unwittingly install the product when they install something else.

Things that Spyware may do to your computer

The capabilities of spyware include taking in any data from a PC users internet history. This means they can hack into their accounts like eBay, Banking, and E-mail.
It can also create endless pop-up ads that make your Web browser so slow you wont be able to use it any more.

Ways of protecting yourself from Spyware

  1. Be Careful Where You Download
  2. Read the End User License Agreement
  3. Protect your system with antivirus
  4. Read before you click on 'run'




Computer worms are Malware computer programs that keep replicating themselves.They also use the network to send the other computers that are connected on the same network.

How do they get on your machine?

Unlike computer viruses, they do not attach themselves to an existing program. However they do still replicate and can are annoying.