Web Applications

As the web is evolving from simply serving up pages, to providing access to dynamic information from a wide range of systems, the sites that a user may access begin to look more like a traditional application, such as one written in Visual Basic or Powerbuilder. In ASP, each virtual directory on the server, which we first saw in Chapter 1 , may also be an application as well (depending on whether you've specifically created it as an application). All of the pages in that directory, whether static or dynamically generated, are part of that application.

Now with most applications, for example an e-commerce shop front for automobile spare parts, you'd ideally have a profile of each user. In fact it almost goes without saying you'd want to be able to track each individual user as you'd want to put together a bill of the items they've purchased to date, what their address and credit card details are and so on. In fact there's a range of questions that you'd probably want to know such as:

• How many people are coming to our site?
• Who are they?
• Where are they coming from?
• How long are they staying on our site?
• Where do they go as they move through the site?

It might come as a bit of a surprise that the HTTP protocol on its own makes no provisions for doing any of this, as it cannot distinguish between users.