Do Not Track is a technology and policy proposal that enables users to opt out of tracking by websites they do not visit, including analytics services, advertising networks, and social platforms. At present few of these third parties offer a reliable tracking opt out, and tools for blocking them are neither user-friendly nor comprehensive. Much like the popular Do Not Call registry, Do Not Track provides users with a single, simple, persistent choice to opt out of third-party web tracking.
(Text from donottrack.us used under their Creative Commons Attribution 3.0 Unported License.)
In addition, Hermit can also request all the Web sites that you visit, asking THEM not to track you as well. This gives you even stronger protection against user tracking and helps maintain privacy.
Do Not Track is a relatively new Web standard, and many sites are continuing to build support for it. Here is a partial list of sites that support Do Not Track.
For example, Twitter has made a commitment to honor Do Not Track: