Protect yourself on the internet

Every time a device of any sort connects to the internet it is assigned a unique IP address. It is possible to have the same IP address assigned to a device every time it connects but often a new address will be assigned.

Let's say I connect to the internet and visit some dodgy websites. During my visit my IP address is recorded and the dodgy websites start scanning my IP address looking to try and hack my system. They are unsuccessful but the IP address is kept as a possible target. I disconnect and next time receive a different IP address.

Someone else connects to the internet and gets assigned the IP address that I used when visiting those dodgy sites. They now become the target of the hackers attention without visiting any dodgy sites and possibly practising safe internet use.

I have no idea if this is how it works or not but from what I have picked up on the 'net you can be a target anytime so it pays to protect yourself at all times.

There are plenty of free options such as Spybot S&D, Adaware (Anti-spyware), Zone Alarm (Firewall), AVG antivirus all for Windows. Mac has a reasonable firewall built in and you can use ClamXAv antivirus - yes it's worth having antivirus software on a Mac. There are plenty of options for Linux as well but I don't know much about Linux.