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 from the method used to store and retrieve that data.

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


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 information such as the following:
  • System metadata, including the object ID and name, the name of the container or bucket, the tenant account name or ID, the logical size of the object, the date and time the object was first created, and the date and time the object was last modified.
  • The current storage location of each object copy or erasure-coded fragment.
  • Any user metadata associated with the object.
Object metadata is customizable and expandable, making it flexible for applications to use.