Ransomware is a piece of software that encrypts all your files and asks for payment to unlock them. It can sometimes be removed, with enough time and effort, but it depends how its been coded. Windows and MacOS have more conventional backup options that let you copy your files over to an external device on a schedule. Alternatively, you can pay for a service like CrashPlan, Carbonite, or Backblaze, where the entire contents of your hard drive are sucked up to the cloud and kept safe.”]
Source: https://gizmodo.com/a-solid-backup-system-is-the-best-protection-against-ra-1795682989