HTTP Headers

What are HTTP headers?

The client and the server can pass some additional information using HTTP headers through a request or a response.

An HTTP header is basically a key-value, where its key is a case-insensitive string and value is a single or array of string.

Types of HTTP headers

These are grouped into different categories below, based on their context:

• General headers: this is used for both request and response and there is no relation to the message data.

• Request headers: these are client headers, sent during the HTTP request and they contain information about the resource to be fetched.

• Response headers: these are server headers and are part of the HTTP response. They give more details about the server resource context.

• Entity headers: these headers give meta-information about the content of the body of the message like MIME type, Content-length, etc.

To learn more about various HTTP headers options, please go here.