What an object is

With object storage, the unit of storage is an object, rather than a file or a block. Unlike the tree-like hierarchy of a file system or block storage, object storage organizes data in a flat, unstructured layout. Object storage decouples the physical location of the data that is stored from the method of storing and retrieving it.

Each object in an object-based storage system has two parts: object data and object metadata.


Object

Object data

Object data might be anything; for example, a photograph, a movie, or a medical record.

Object metadata

Object metadata is information describing the object data. Object metadata includes a bucket/container and key, which together uniquely identify the object. Metadata also might include such information as last access time, modification time, and storage location. The metadata is customizable and expandable, making it flexible for applications to use.