This complements with backup software.
For your backups (and also any data in general, but see backup software discussion about the type of data) you want to have some appropriate hardware.
That can include offline media, like tapes, DVDs etc (or even hard drives which you archive).
Or it can be online / live, and then usually accessible via network in some way. This is then called a Network-attached storage (NAS) system -- or at least, a NAS is very related.
Never use hardware RAID but always software RAID. ZFS scrub.
Some references:
- Modular, extensible DIY NAS: Building the perfect, cheap DIY NAS, 2020. HN discussion
- Installing FreeNAS on my QNAP TS-459, 2020 (HN)
- Tape
- Linear Tape-Open (LTO), Wikipedia
- 400 TB Storage Drives In Our Future: Fujifilm, 2020
- LTO8: 100€ for 30TB, 30 years.