206 Partial Content
Meaning
The server is delivering only part of the resource due to a range header sent by the client.
When to Use
When fulfilling a request with a Range header, returning the specified portion of the resource (used for resumable downloads or splitting downloads).
Example
GET /file.zip with a Range header returns 206 Partial Content with the requested byte range of the file and a Content-Range header.
When Not to Use
Do not use if no range was requested or if the full content is being delivered (use 200 for the entire content).
Source
RFC 9110