An explanation of cookies

Cookies

A 'Cookie' is simply a piece of information that is stored on your local computer by a webserver. There are however 2 different types of cookies, and there purpose, use and problems depend on the type.

The first type are session cookies, and are used to hold information temporarily, and ONLY exist for as long as that particular web browser window is open. As soon as it's closed, they are deleted. For instance, most websites, ours included, will create a session cookie so that the server can keep track of which shopping cart belongs to what connection ( which is why you need to have them enabled to put items into the cart, otherwise nothing happens ). Also they're used to store information when running search's so that the information persists. Session cookies are pretty much harmless, since they only exist for as long as you have the specific browser windows open.

Persistent cookies on the other hand can present some problems, but mostly from the point of view that they can be used to track your browsing habits across multiple sites, but only if the sites use the same system, advertising or the like, for example Doubleclick and Hitbox, but there are numerous others. Now for most people, that isn't really important, and they do have other uses, which are potentially very useful. In many cases they are used to keep your user information, to speed up login or ordering, such as our system which stores your address details on your own computer, so if you return to our site, it can automatically fill in the address information. The 'danger' that most people are concerned about is that somebody could compromise your system and get at such information ( ignoring the fact that most of it's encrypted, and in our case highly encrypted ), but it would need someone to either compromise browser security ( a cookie is normally only accessible to the site that created it ), or install a Trojan program on your system, which are probably less likely than the current crop of email scams that are out there. On top of that, most companies are not really stupid enough to hold any really important details in something they don't have direct control over. There's not anything stored in the cookies we create that couldn't normally be found by looking in the phone book. Finally most persistent cookies have a timeout, after which they are flagged as being invalid and deleted.

So to summarise, session cookies should be allowed, since they are transient, and fulfil a useful function. Persistent cookies are also useful, but it's worth keeping any eye on them, and clearing them out every so often. About the only thing I normally suggest blocking are third party cookies, mainly to just annoy and frustrate the advertising sites, more than for any particular reason.