Twitter has started using cookies to track information about where the user is logging in from, as well as information on what other sites they have visited recently. The same techniques have already been used by Google, Facebook, Amazon, and Twitter is the last to join the advertising band wagon. Twitter is valued at approx $10 billion, and has supposedly bumped up its advertising capabilities in face of an anticipated initial public offering in 2014.
Twitter will allow retailers to attach anonymous versions of their customers email addresses, called hashes, to Twitter's advertising engine so that it can individually target the customer base. Twitter's new feature is expected to raise advertising rates and revenues for the company.
In recent years there has been an increased debate regarding internet security and users privacy. European Union as well as the U.S. Federal Trade Commission has looked into the extent of tracking technologies on Facebook, etc. Last year, European authorities have asked websites to inform visitors that cookies have been placed on their computers.