Thu, 04/09/2008 - 21:03 — horuskol

Logging into an online discussion forum and browsing the threads before posting replies to one, some or all, is an activity that most people just do these days without even thinking about it. Even shopping on a site like Amazon, which remembers your shopping basket as you browse for one last book/movie/gewgaw to purchase and get your order total high enough to achieve the free delivery option without even logging in until it comes time to part with your cash is a non-event these days.

Most people don't stop to think about how this is possible - it just is. You don't ask the shopping basket in your local supermarket how it remembers if there are carrots and peas in there already before you pickup the potatoes, so why is the internet shopping basket any different?

Creation - Destruction - Creation

What most people do not realise is that the internet has no memory!

Well, okay. There are search engines which store copies of web pages from times gone past, and if you have already visited this site and commented it will still be there the next time you come along.

What I mean is that the underpinning protocol of the internet, the HyperText Transfer Protocol (HTTP), has no inherent ability to remember things. It is what is called a stateless protocol, which means that once a new request is made (by clicking a link or posting a form), the new page doesn't know what was happening on the last one. This is because of the architecture used in connecting your computer by cable to a server in some unknown location and getting a web page from there to you.

Now, you and I know that this is not what seems to be really happening - your logins are remembered on the message boards, and your prospective purchases are remembered in the shopping basket.

Read on to find out how: