Despite claims by the insecurity industry that your computer will be possessed by viruses in seconds if you don't buy their software, modern computers are fairly safe without them.
According to the British consumer watchdog magazine Which?, computers are less susceptible to viruses and other threats than many users might think. The study found that not one of five computers connected to the internet for four weeks became infected, despite figures suggesting an estimated 60,000 new malware threats occurred daily.
Each machine was used to visit a list of 22 "reputable" websites, ranging from Amazon.com to Tesco.com, for an hour a day. The consumer group said it did not overload the PCs with security software, describing one as such an easy target "it was practically saying come and get me".
Of course the computers were not programmed to visit unsafe sites so the moral of the story is don't visit immoral sites. Or open email, which is another thing that the test did not do.