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 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.
Common follow up questions
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