Ransomware

Ransomware is a business, and the business is extortion. Criminals lock up your files and ask for money to unlock them.

The part that has changed is that locking the files is now only half of it. Before anything gets locked, the data is usually copied out first. So even if you can restore everything from a backup and never pay, they still hold your information, and the second demand is to pay or they publish it. That is why "we have backups" is no longer a complete answer. The question is also what was taken, who it belongs to, and who you now have to tell.