NAS

A NAS (network-attached storage) is a small computer whose main job is to hold disks and share them over the network. Instead of plugging a drive into one laptop, you connect the NAS to your router, and every computer, phone and TV in the house or office can open the same folders, as if they were a shared drive.

People use a NAS for family photo archives, automatic backups of every computer, a media library the TV can stream from, or shared project folders in a small office. Most NAS boxes hold two or more drives and can mirror them with RAID, so if one disk dies the files are still on the other. Many also run apps: photo galleries, file sync like a private Dropbox, or remote access from outside the home.

A NAS gives you a lot of storage that you own, with no monthly fee, but you are also its administrator. A mirrored NAS still is not a full backup: a fire, a theft or ransomware can take everything at once, so important files should also have a copy somewhere else. Exposing it to the internet without updates is a common way to get hacked.