HTTP header fields are components of the message header of requests and responses in the Hypertext Transfer Protocol (HTTP). They define the operating parameters of an HTTP transaction. The header fields are not directly displayed by normal web browsers like Internet Explorer, Google Chrome, Firefox etc. Below is the HTTP Header information of blog.xkcd.com:
HTTP/1.1 200 OK
Date: Tue, 10 Oct 2017 09:02:27 GMT
Content-Type: text/html; charset=UTF-8
Last-Modified: Tue, 10 Oct 2017 08:57:40 GMT
Cache-Control: max-age=13, must-revalidate
X-hacker: If you're reading this, you should visit automattic.com/jobs and apply to join the fun, mention this header.
Link: <http://wp.me/5mNqq>; rel=shortlink
X-ac: 1.ewr _dca
blog.xkcd.com - DNS Record Analysis
Domain Name Systes (DNS) translates easily memorized domain names to the numerical IP addresses needed for the purpose of locating computer services and devices worldwide. There are total 16 DNS record(s) of xkcd.com.