Passwords stored in cookies should always be encrypted. There's also the question of how Web sites use specific demographic information. Let's say you run a site that happens to contain information on how to make pipe bombs or grow marijuana. The answer varies from country to country, but for some people, this makes accepting a cookie the equivalent of being under surveillance. What you can do Depending on how they're used, cookies may or may not be a threat to your privacy.
Users can then usually look over a cookie's contents before accepting or denying it.
Most cookies don't contain anything more than a tracking number, or a username and encrypted password. If you use this option, you may choose to set only those cookies you find valuable or that come from a site whose reputation you respect. Of course, there are so many Web servers using cookies today that it can quickly become too annoying to accept or deny each and every one - especially when surfing a site that attempts to set several cookies per page. You can force most browsers to refuse all cookies with a simple trick - make the file where your browser stores its cookies nonreadable. The trade-off will be that you may lose some of the added functionality cookies provide.