Storage
Block Storage
Raw disk volumes you attach to a server and format like a physical drive, used for databases, filesystems, and boot disks.
Block storage gives you a raw volume that behaves like a physical disk. You attach it to a server, format it, and mount it, then read and write at the block level with low latency. It's what your operating system boots from and what a database wants underneath it, because random reads and writes stay fast.
The useful trick is that block volumes are separate from the server. On DigitalOcean, Vultr, Linode, and Hetzner you can detach a volume from a dying instance and reattach it to a fresh one, keeping your data while the compute changes. Volumes typically run a few cents per GB per month, with Hetzner around the low end at roughly a few dollars for 50GB.
Block storage is for data one server accesses directly. When many servers or users need the same files, or you're storing millions of objects, object storage is the cheaper and more scalable tool.