You own the servers. This is a tool to build your own object-storage cluster. For example, you can get 3 old desktop PCs, install Linux on them, download and launch Garage on them, configure your 3 instances in a single cluster, then send data to this cluster. Your data will be spread and duplicated on the 3 machines. If one machine fails or is offline, you can still access and write data to the cluster.

Then, how does Garage achieve 'different geographical locations'? I only have my house to put my server(s). That's one of the main reasons I'm using cloud storage. Or is the point that I can arrange those servers abroad myself, independent of the software solution (S3 etc)?

Garage is designed for self-hosting by collectives of system administrators, what we could call "inter-hosting". Basically you ask your friends to put a server box at their home and achieve redundancy that way.

Is the data encrypted at rest, or should I encrypt the data myself?

The content is currently stored in plaintext on the disk by Garage, so you have to encrypt the data yourself. For example, you can configure your server to encrypt at rest the partition that contains your `data_dir` and your `meta_dir` or build/use applications that supports client-side encryption such as rclone with its crypt module[0] or Nextcloud with its end-to-end encryption module[1].

[0]: https://rclone.org/crypt/

[1]: https://nextcloud.com/endtoend/

Great, thanks. It would be great to add this in the main explanation (how to get access to servers).