Apple is working on adding a Do-Not-Track option to Safari, following in the footsteps of other browser vendors who have already implemented such solutions.
Last year, the Federal Trade Commission (FTC) called for an uniform do-not-track browser setting that people can use to express their desire not to be tracked online.
Visitor tracking across websites is something that all advertising networks currently do in order to serve more relevant ads.
But under current conditions, if users want to opt out of this behavioral advertising, they need to install special browser cookies for every advertising network that supports them.
Also, advertisers are not legally required to honor people's requests or to make opt-outs available. The ones that do, have generally agreed to act under principles laid out by a trade association.
The FTC wanted a uniform solution so that relevant legislation could be built upon it, but browser vendors went ahead and came up with their own implementation.
Mozilla introduced a DNT (Do Not Track) HTTP header which is sent along with every browser request, Microsoft opted for a more pro-active solution based on block lists, while Google designed an extension making the management of opt-out cookies easier.
Of these solutions, Mozilla's header seems to be the easiest to standardize and has already started seeing some adoption. Microsoft also included the DNT header in its submission to the W3C.
According to a Wall Street Journal
report, Apple is working on a similar option in Safari, the feature already being available in the browser's version included in Mac OS X Lion developer preview.
Its not immediately clear how the Safari do-not-track feature works in detail, but the move leaves Opera as the single major browser that doesn't have such an implementation at the moment.