A Web cache sits between one or more Web servers (also known as origin servers) and a client or many clients, and watches requests come by, saving copies of the responses — like HTML pages, images and files (collectively known as representations) — for itself. Then, if there is another request for the same URL, it can use the response that it has, instead of asking the origin server for it again.

Do Not Track Plus
Stop companies from tracking you
Ad companies and social networks are tracking everything you do on the web. They know what sites you visit, when you visit them and how often you do...and they know who you are. DNT+ blocks the tracking so you can browse freely and safely.

This document specifies relation types for Web links, and defines a registry for them. It also defines the use of such links in HTTP headers with the Link header-field.