For many thinking about an SHTF situation involves making sure there is plenty of food storage and that they have plenty of guns and ammo. That is all important of course, but living in a highly technology-centric society means that much of what me do is digital. Living in a digital world like this means if an adversary wants to cripple us, they can just knock out our technology infrastructure and cause havok, think about what happened during Y2K, and if you're too young for it look it up. So, in order to be properly prepared we also need to think about the technology we have and how to prepare the data that we may not want to lose for such a situation. We do have a few options on how to do this and using more than one is very beneficial.
Hard copies is probably one of the easier ways, but also very space intensive. This I would recommend for key documents; medical records, identification docs, even family pictures, and journals. It takes up paper and space, but this guarantees that if something like an EMP hits, you don't lose everything for your family history or for a medical emergency. This can also mean currency, since much of our transaction now happen electronically, but plenty of people have talked about having cash of hand in case of such situations.
In this category, I would also include reference materials for tools and vehicles. If you can't get to a shop to fix something and the internet is down, you'll be glad you had that book on you. Cuba is a great example of this, while under Fidel Castro, they had books and guides that helped them learn to fix the appliances they had. From such books they figured out how to repair fans and even recharge hearing aids. The skills you can learn from these books in priceless, especially when you can't just look it up online, I would also recommend at least reading through them once.
Also, add in fictional literature in here, since you'll have a lot of time to read. Your kindle or iPhone won't last long if you don't have a way to recharge it, or if you're keeping a low power profile. Having a few good books you know you will reread again or a few you haven't yet read will fill in down time and help ease your stress.
For situations where the grid doesn't completely go down, having backups stored away means you don't lose everything and you should take time to update backups as needed. There is plenty of software out there to automatically backup your data to an external storage device, but I'm not talking about that, I'm talking about your EMP-proofed/buried backups. Luckily, this option has gotten much less space intensive with advances in technology. Also, as an added note, a situation where this would be viable is the more likely one, in my humble opinion, due to the usefulness of location tracking and how it is done today.
Our options for easy to obtain backup medium has expanded quite a bit with how prolific the smartphone has gotten during the 2010s. Many of our option can store hundreds of terabytes of data in a small box. Options like these are best:
Each of them has their own advantages and disadvantages.
Solid states drives (SSDs) are an improvement on the hard drive, they store data on chips much like flash drives and don't have any moving parts like a hard drive does. They are also typically smaller is size than a hard drive, meaning you could store away more of them in a lead box than you could hard drives. The disadvantage with them is, and the other options I've listed, is that electic shock can kill the data on them. Depending on whether you get an internal or external you could have a bulkier package, but the option for external SSDs means you can plug them into a USB port to access your data. They fit well in cargo pockets or backpack pockets generally, too, for those that wanna take their data on the go.
Usually called a "Thumb Drive" due to their size normally being that of a thumb, they are quite easily pocketed and a favorite tool of pentetration testers as a social engineering exploit. With the advances of flash memory, as I have noted, these little drives have gotten much bigger from their 512MB sizes from over a decade ago. People often use them for school homework and some medical documents, now. This is an excellent option from having on your person or to squirrel away in your bags somewhere. They have the same advantage of an external SSD in that they can plug into a USB port easily, but they can be quite fragile if bumped just right. You should be able to easily find these drives in 1TB sizes and if not, 256GB is still quite common to find, and that will hold plenty of PDF docs.
These ones and very much like flash drives, but are made with the intent or inserting in your smartphone of game console. They don't have a USB interface, so you need some sort of reader for them to access the data from your computer. They do have a huge advantage of being extra small in size however and are very easily concealed. That concealment factor is much more easily seen from S2 Underground's SERE Kit video. They do come in 1TB sizes as well, so you can stick quite a bit of info on them and partition them out so you can hold encrypted data on them. They can be pricey depending on the brand you pick up, but guaranteeing that you have the space you need can sometimes be a boon, so I highly recommend getting a reputable brand like SanDisk and making sure you have bought it from their store.
The interface on the SD cards does mean you can access the data from a smartphone that has a slot or from a portable device that does as well. Many more devices with full desktop computing functionality, like the Steam Deck, exist that allows you to access that important data whereever you are or to access the data of others. These devices also have much more power than even many smartphones, to allow for much quicker access to weakly encrypted data.
Having data backed up is all fine and dandy, but what happens if someone takes your computer or smartphone? What if your computer gets fried? How do you access your backup data now? This takes a bit more preparation, but is quite easily done and has plenty of affordable (and expensive) options.
The Raspberry Pi is a single board computer that has a low power footprint. It easily runs off of a USB power backup. Depending on the model you get, it has a number of USB ports and an HDMI port. It uses an SD Card for the main boot medium. These are quite available on amazon with entire kits for the hobbyist. On the SD Card you decide to use for the Operating System, I would recommend a version of Linux and occasionally taking time to make sure it is up to date. What is nice about the Pi is that it can easily store in a small box. Yes, you can put the Pi in a lead box with your precious data backups. Once, you boot up your Pi, however it is powered, you should be able to open a file browser and plug in your data backup to access your data. If you want to, you can backup your data directly to the SD Card you are booting from.
If you have been using computers for a while, you've probably bought a new up-to-date computer because software and hardware continuously improve. Those old computers can be used as backups or ways to access your backups. If you have old laptops, these make excellent ways to stow away data. Many laptops have SD Card slots, so you can plug one with your backups into it. Again, laptops and old desktop computers make great places to backup your data as well, if you buy a new SSD for them, they even get a new breath of air.
Now, what if your computer doesn't support the latest update of Windows? Scrap the idea of Windows on that old computer, install Linux, it runs quite well on old hardware, just ask any Thinkpad enthusiast. Again, much like a Raspberry Pi, I would recommend taking that computer out on ocassion and making sure your software is up-to-date. Linux has software to let you look at most if not all of your data.
Data is a precious resource, ask any big tech company. If you take the time to work out how to make sure your data is still available, it will benefit you and you won't feel lost or stressed. Also, if someone happens to "lose" your records, you still have them to make sure they have them. This can mean life and death in a world where you never know when you're the enemy.