Not sure what information is being passed by your web browser to a site you are visiting? This small utility displays all request headers being passed by a web request sent to network-tools.org

Accept text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Encoding x-gzip, gzip, deflate
Host www.portcheckers.com
User-Agent CCBot/2.0 (http://commoncrawl.org/faq/)

Browser request to a web server

When you open a page through a browser, typing in the address bar, there is a connection to a remote server, usually to port 80. Such a request is called GET-request - this is one of the main types of HTTP-protocol requests. Sending a request, as well as its contents, usually hidden from users, but there is nothing secret about them.