Dynamic Web Pages
Dynamic web pages come in two flavours. The most obvious are those that actually do something on the screen, like turn buttons different colours, or include some animation. The less obvious, are those that interact with the customer.
Say you had more products, services or options than could easily be shown on a single static web page. We could create a static page for each combination, but if there were a hundred combinations the cost of that many static pages would be very high. However we could just create one dynamic page, which varied depending on the options the customer selected. This one dynamic page could be half the price of creating the hundred static pages.
Dynamic pages are more expensive to maintain, but compared to a hundred static pages the
initial costs are worth it for a large catalogue.