There are a few HTTP headers that are specific to responses. They provide information related only to the nature of the response and not the content.
The Accept-Ranges header is the only HTTP header in the Accept family that is not a request header. This header indicates to the Web client that the server has the capability to handle range requests. A Web client can make a range request using the Range request header.
There are only two valid formats for the Accept-Ranges header that are allowed according to the definition:
Accept-Ranges: bytes Accept-Ranges: none
These basically indicate that the Web server does and does not accept range requests, respectively.
It is not necessary for a Web server to indicate ...