Internet: Use anti-virus software and anti-spyware/malware software to be safe.
Anti-virus software and anti-spyware/malware software are important. They help protect your computer when you're connected to the internet. They can also stop you running a file that could infect your machine with a virus.
But the problem people have isn't downloading these two pieces of software. So if you just ignore them then they're virtually useless.
You have to use them! There are so many people who never update their anti-virus/anti-spyware software. Or how many just skip the virus scan when it starts.
The threats out there are real. Many thousands of people are infected every single day and people need to make sure they do what they can to make sure their computer is clean. The simple task of keeping the software up to date and running it regularly could save your personal data.
Also, make sure automatic updates are switched on. Advanced users can leave automatic updates are off - that way they can check which updates are available and which they want to install.
But for people who have never manually checked for updates should switch it on. That way urgent patches delivered by Microsoft to plug security holes are automatically downloaded and installed providing you with better protection.
Though none of the above is fool-proof. You can do all this and still be infected - especially if you have bad habits like opening *.exe files that are sent to you via e-mail or you automatically open every e-mail even if it's not from someone you recognise. Or browse to sites that utilise unpatched security holes to infect your PC.
But if you do the above regularly then you can minimise the chances of suffering at the hands of the next botnet attack.