# Headers

* Headers contain the metadata for an API. 
* Headers are defined for the Request body and Response body.
* There can be multiple headers for an API.
* The header for an API comprises the following fields: 
  1. Header Name: This is the header's name. A header always has a unique name and conforms to the variable name rules. This name will be used when working with the header value in Actions. 
  2. Header Text Name: This field defines how the header name would appear in the request received or in the response. It can be the same as the Header name or a different text as to how the header should appear. 
  3. Header Type: This section defines if the header information/metadata will be related to either:
     * Request: The header is only available in the request information. 
     * Response: The header is only available in the response information. 
     * Request and Response: The header is available for both the request and response.
  4. Documentation Data Type: This field is for documentation reasons so that the developer of the API can advise the users of the API on what data type the header values should be conformant with. 
  5. Value of the Header: This field contains the value of the Header. This is the value placed on the right side of the ‘:’ e.g., Content-Type: application/json 
  6. Header Example: This field can be used to write an example of the header. 
  7. Parameter Description: This field can be used to describe this parameter.

{% embed url="<https://media.langstack.com/documentation/media/images/code/training_manual/chapter_4/ch4headerlabel.png>" %}


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