The latest trend in organised cybercrime that targets everyone from large businesses to home users: Ransomware!
What is it? It’s malware (possibly a virus or a trojan) that will silently encrypt files on your computer and network servers. Once encrypted they are impossible to open without being decrypted first. To get the decryption key you must pay the group who wrote the malware usually in untraceable bitcoin.
How could I get it? The same way you would get any virus or malware, through malicious email links or attachments, browsing to a malicious or hacked website or installing software that is malicious.
How do I avoid it? All the usual safe computing practices will help – keep up-to-date on software and operating system updates, run good up-to-date antivirus and a firewall, don’t open any suspicious or unexpected emails or click any suspicious links. But very importantly take regular backups (and test they work!) as restoring from backups is often the only way to get your files back if you get hit by ransomware.
Here is a great video on ransomware from the BBC.
Stay safe, watch out for suspicious/unexpected emails, don’t click on unknown links and TAKE REGULAR BACKUPS.