Ransomware isn't your typical computer virus.
It's a type of malware that takes a hold of a device and then requires that user pay a fee to the hackers to get rid of the virus and even then there's no guarantee that they'll fulfill it.
One reason hackers are able to get into the systems so often is that people tend to avoid regularly updating their computers. The longer you put off those crucial updates the easier it is for hackers to get around them.
You might want to consider buying an external hard drive if you don't already have one. You can back up any important files you already have on your computer onto it. So if a hacker does take control of your computer, you won't have to pay them to get your information back.