1. Virus code actions Or ‘how viruses work’

2. Replication Spreads quickly and can be difficult to control Can be attached to any type of file and make copies of itself Can be programmed to operate at a certain date meaning it has more time to spread to lots of computers

3. Camouflage Less likely to spread and easier to control as detection software has evolved to stop this happening Can be done with false coding – bits of bad code mixed with good code – so that it has the same characteristics of a normal program Appears to be a harmless program – used by trojan horses

4. Watching A virus that waits for an action or a date before acting Usually happens when doing something routine It can only happen if the conditions are met

5. Delivery Easy to get – can be caught through internet connections, infected disks or memory sticks, downloads from peer-to-peer sites such as napster Once it is delivered it will wait for the trigger to set it off It is mainly used to transport viruses