As always, after updating the operating system and any applicable protection software, the best line of defense is a complete backup of your computer.

Macintosh users should utilize the built-in Time Machine backup software. With the exception of a few system settings, Apple Time Machine can restore your Mac or migrate to a new one as if nothing had changed. In the case of a new computer, you get the benefits of the latest OS, with all your existing files and programs intact, and exactly where you left them.

Windows users have many choices, but we prefer Acronis True Image for it's ability to return the system to a state where it would seem nothing had ever happened, and for painless migrations to new machines when it's time.
While any backup at all is a good backup, redundant backups are always better. Ransomware can often attack ALL drives that are attached and mapped to the operating system. Keeping data on a separate drive that is not connected is one method, but the problem we see often is, people forget to plug it in, so their backups are out of date. A single backup drive is also a risk when it's used for double purpose. We see this often with laptops that don't have enough storage space. Data, photos and videos end up on the backup drive because it has lots of free space, but then it's only in one place.

Drive failure is also a very real risk. It's a great feeling when we're able to recover data from a hard drive that has started to malfunction. Our clients are happy and that make us feel great too. Unfortunately in some cases, it's not possible.

With drives that won't spin up or with some solid state hard drive failures, the only choice is an expensive recovery service. Expect companies that specialize in data recovery to charge anywhere from $500 for just a small amount of your data to $1000 or much more, depending on how much data has to be recovered and how difficult the steps required are to get it back.
Don't fall into the trap of not backing up because it's inconvenient. If you know you're not disciplined enough, don't have the time, or simply don't want to spend a lot of time manually duplicating backups, take action and get a reliable automated solution. It's painful when we can't recover a drive that had our client's family photos on it, but we know our pain is nothing compared to what they are feeling. Most can't afford to take their faulty hard drive to one of the expensive recovery services, so it makes sense to invest in comparatively inexpensive automated backup solutions

Theft and fire are also very real risks. When a client recently came to us with the news of a stolen laptop and a single backup drive that could not be accessed, we were happy the story ended well and we were able to recover the 5 years of data they had backed up on that hard drive. They made the smart choice of purchasing a Synology NAS (Network Attached Storage) drive after that experience.

In March 2017, we wrote about the benefits of a NAS (Network Attached Storage) drive to reduce dependency on cloud backups, but these devices are also capable of automatic redundant system backups, including one of them on a cloud drive for automatic off-site backup.