What's the Latest Development?

Cookies are delicious chunks of text inserted into websites that identify a user when he or she returns to the site later. Cookies have benefits, to be sure, but there is a less savory commercial side. "They are used to track behaviour, and so target advertising. Cookies let marketers pinpoint the sorts of offers likely to attract a particular user. That lets sites demand higher fees for virtual hoardings." Experiments with cookies have shown they can be inserted into the least obvious nooks in a computer and replicate themselves if not deleted.

What's the Big Idea?

While instances of cookies are becoming less frequent—an independent group has noted a substantial reduction in privacy-invading behaviour by the 100 most frequently visited websites—tracking devices are advancing faster than browsers' privacy features can coax them out of hiding or block them altogether. But cookies are only good for business when they are kept hidden. When it was revealed that Hulu, Spotify and Gigaom were using persistent-tracking and respawning methods, the companies immediately desisted.