A dynamical website is so much more than a website where the address of your company can be found, or the company brieflet can be downloaded. A dynamical website can enable users to search through your product catalogue or scroll through the offered products. Also a completely automatic webshop is one of the possibilities.
Other examples are a forum or a poll on the internet, or daily news messages available through different media such as rss, email or the website itself of course. All database information can be presented in many different ways to your users, making your website a pleasure to visit.