Cookies are small snippets of computer code saved on your computer so the next time you visit the site that store information about what you've done on that website in the past.

Cookies could be a good thing or a bad thing, depending on how the website designers use them:

Good things:
  • Cookies can help determine what kind of information is displayed on a page, based on information you've clicked on in the past.
  • Cookies can be useful on shopping sites to remember what you had in your cart the last time you were shopping there.
  • Cookies can help keep track of things you are interested in on a particular website

Not-so-good things:
  • Cookies can keep track of everything you've ever searched for on a page--that could be invading your privacy.
  • Cookies can be a sort of spying software installed on your computer with your permission(!) by visiting a website.
  • Cookies can collect personal information you enter on a website.

And furthermore...cookies can help determine what kinds of advertising shows up on a page.