Object Storage

In Turkish: Nesne Depolama

Updated September 30, 20263 min read

In short

Object storage is a way of storing data as whole objects, each with a unique key and metadata, in flat buckets that scale to huge numbers of files over HTTP.

What is object storage?

Object storage keeps data as objects: each object is a blob of bytes, such as an image, video, backup, or log archive, together with metadata and a unique key like invoices/2026/09/42.pdf. Objects are grouped into buckets, and instead of a hierarchy of real folders, the namespace is flat; slashes in keys only make it look like folders. Applications read and write objects through an HTTP API, so any server, script, or browser with permission can reach them.

The API is deliberately simple: put an object, get an object, list keys with a prefix, and delete an object. Objects are usually written whole, so to change one byte you upload a new version rather than editing in place. In exchange, object stores spread data across many machines and often several data centers, offering very high durability, practically unlimited capacity, and a low cost per gigabyte; many services and open-source systems implement the S3 API, which has become a de facto standard.

Object storage is the usual home for user uploads, static website assets, media files, backups, and data lakes, and it pairs well with a CDN for delivery. Presigned URLs let a browser upload or download one object directly with a temporary signed link, so large files don't pass through your own servers. It is like a coat check: you hand over an item, get a ticket with a unique number, and later use that ticket to get the exact item back, without caring where on the racks it was stored.

Object storage is often confused with file storage and block storage. A file system offers folders, file locking, and in-place edits for programs that expect a disk, and block storage presents a raw virtual disk to a single server, typically for databases and operating systems. Object storage gives up those features in favor of scale and HTTP access, so it is a poor fit for data that changes constantly in small pieces, such as a database's own data files.

Key takeaways

Object storage saves data as objects: bytes plus metadata, addressed by a unique key.
Objects live in buckets with a flat namespace and are accessed over HTTP.
Objects are replaced as a whole rather than edited in place.
It offers high durability, huge capacity, and low cost, which suits media, backups, and data lakes.
File storage offers folders and in-place edits; block storage acts as a raw disk.

Example

Uploading a file straight to a bucket with a presigned URLjavascript

// Your server creates a presigned URL: a temporary link that allows one upload
const { uploadUrl, key } = await fetch("/api/uploads", { method: "POST" })
  .then((r) => r.json());

// The browser uploads the file directly to the bucket over HTTP
await fetch(uploadUrl, {
  method: "PUT",
  headers: { "Content-Type": file.type },
  body: file,
});

// The object is now stored under its key, e.g. "avatars/user-42.png"
console.log("Uploaded as", key);

Readers ask

What is the difference between object storage and a file system?

A file system organizes data in nested folders and lets programs edit files in place, lock them, and open them like local files. Object storage uses a flat namespace of keys in buckets, is accessed over HTTP, and replaces whole objects instead of editing them, which lets it scale much further at lower cost.

What is a bucket in object storage?

A bucket is a named, top-level collection of objects, similar to a drive or a root folder. Access rules, region, versioning, and lifecycle policies, such as deleting old files after 90 days, are usually configured per bucket.

Should I store files in a database or in object storage?

Large files such as images, videos, and backups usually belong in object storage, with the database storing only the object key and metadata. This keeps the database small and fast and lets files be served efficiently, often through a CDN.