Synology. QNAP is good too but Synology is probably the easiest to use and they have very strong and long-standing software support.
Edit: QNAP has had some security issues too. I’ve had Synology gear for close to a decade, interspersed with DIY servers and homelab stuff and really, really like it. If I were getting my parents a NAS/backup system, that’s what I would get.
Edit: QNAP has had some security issues too. I’ve had Synology gear for close to a decade, interspersed with DIY servers and homelab stuff and really, really like it. If I were getting my parents a NAS/backup system, that’s what I would get.