The HTTP Headers Check returns the headers that a web address shares with the client when visiting the specified webpage. The information returned contains information that the device will use to access the website. HTTP header checks are common with developers and server administrators.

Headers are a common component of sending and receiving requests online. The purpose of headers is to provide additional information with each request that helps the server better serve the client. There are several types of HTTP headers:

1. General Headers: Used in both messages from the client to the server and from the server to the client
2. Request Headers: Information shared by the client with the server. This includes the user agent of the device, credentials, host, and referrer.
3. Response Headers: Information about the host that is shared from the server to the client
4. Entity Headers: Contains information such as content type, length, and media type
5. Security Headers: Used to provide security requirements for the client and server

A HTTP Header check will include an array of information useful to developers and server administrators. Additional results may be returned based on the configuration of the server.

HTTP Headers include the following:

• URL: The web address where headers are being checked
• Date: The date and time in which the request was sent
• Content type: The media type of the resource
• Content length: The size of the response body in bytes
• Content encoding: The type of encoding used on the content, such as zip
• Cache control: Instructions on how to cache for both the client and server
• Set-cookie: Cookie being sent to the client from the server
• Last modified: Last modified date of the srouce
• Strict-Transport-Security: Forces SSL/TLS for the connection
• Content-Security-Policy: Security policy meant to prevent a wide range of security issues
• X-Content-Type-Options: Prevents the browsers from being tricked into view the media type as a different type