The Kinds of Storage: Block, File, Object

"Storage in the cloud" isn't one thing. There are three quite different kinds, each suited to a different job, and telling them apart clears up a surprising amount of confusion. Most beginners assume one kind of storage and end up reaching for the wrong one.

A simple analogy maps each type to something familiar. Your desk drawer is attached to your desk and no one else reaches into it — that's block storage. The shared filing room that anyone on the floor can open is file storage. A giant self-storage facility where you label a box, leave it, and can come back for it from anywhere is object storage. Same broad idea of "keeping stuff," three completely different designs.

Block Storage — A Disk for One Machine

Block storage is a virtual hard disk — raw storage capacity — attached directly to one machine. The machine sees it exactly like an internal drive and manages what gets written where. Only that one machine can use it at a time.

This is the right choice when a server needs its own, fast disk: databases and operating systems typically run on block storage because they need direct, low-latency access to every block of data they write.

File Storage — A Shared Folder

File storage is a managed shared folder — sometimes called a network drive — that many machines can mount and use at the same time. Several servers can all read and write the same files in it, the same way employees at different desks share a folder on an office network. File storage manages its own directory structure; software on each machine just sees a normal folder.

Object Storage — Named Files Over the Web

Object storage is a vast pool of individual files, called objects, each stored by a unique name. There is no directory tree; you upload a file, give it a name (called a key), and retrieve it later by that name through the service's API — usually over HTTPS. Access is permission-controlled: objects are private by default, and a URL alone does not mean the object is public. You don't mount it like a drive — you reach it through a web request with the right permissions.

Object storage is built for scale. It holds anything from a handful of files to billions of them, grows without limit, and is the type behind most of what the cloud serves: photos, videos, backups, and static website files.

Which for What?

Each type has a natural home. Block storage belongs under a single server's OS or database — anywhere that needs a fast, private disk. File storage suits shared documents and files that multiple machines must read and write simultaneously. Object storage is the right destination for media, large-scale data, backups, and anything delivered over the internet to many users.