What is object storage like Amazon S3?
Object storage keeps data as objects in a flat space called a bucket, rather than in a folder tree like a normal file system. Each object has the data, some metadata, and a unique key. It is highly scalable and cheap, which is why services like Amazon S3 are used to store images, backups, videos, and other files.
- Object storage keeps data as objects with metadata in a flat namespace.
- It scales massively and is ideal for files, images, backups, and logs.
- Amazon S3 is the best known example, accessed over HTTP APIs.
Object versus file storage
A file system uses nested folders and paths. Object storage has no real folders, just buckets holding objects identified by keys. This flat design scales to billions of objects far more easily than a traditional file tree.
- Highly scalable and durable, with data copied across machines.
- Cheap for large amounts of data.
- Accessed over HTTP, great for images, backups, and static files.
Give a real use case. Saying you would store user uploaded images in S3 and serve them through a CDN shows you know how object storage fits into a real system.
Frequently asked questions
How is object storage different from a file system?
A file system uses a folder hierarchy, while object storage uses a flat space of objects with unique keys and rich metadata, which scales far better.
What is object storage good for?
Storing large amounts of unstructured data like media, backups, and static website files, where you need durability and scale rather than fast edits.
Common follow up questions
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