One of the most controversial topics in our always-online, always-connected world is privacy. Even casual computer users have become aware of how much "they" know about our online activities, whether referring to the National Security Agency spying on U.S. citizens, or the constant barrage of ads related to something we once purchased.
Concerns over online privacy have brought different responses in different parts of the world. In the U.S., for example, many Web browsers let users enable a Do Not Track option that tells advertisers not to set the cookies through which those advertisers track their Web use. Compliance is voluntary, though, and many parties have declined to support it. On the other hand, European websites, since 2012, have been required by law to obtain visitors' "informed consent" before setting a cookie, which usually means there is a notice on the page saying something like "by continuing to use this site, you consent to the placing of a cookie on your computer." Why are these approaches so different?