Once a static website has been published it will not change until the next edition. A dynamic website, on the other hand, relies on a back end engine to change site content. Dynamic site content is changed on the fly while static content modified through editions. Deciding whether static or dynamic sites are better is like determining whether vanilla or chocolate ice cream is better. It truly depends on your situation, and your needs.
Dynamic websites yield more to the interactive makeup of the Internet. Because dynamic site modification does not require knowledge of html, it simplifies editing. Users are empowered, for they are enabled to make changes to the site.
The decision is yours to make, and it should be based on your needs. Most websites are infrequently edited, and, unfortunately, are not at all interactive. Therefore, a static site is the logical choice. For example, if you are an insurance broker and you just want to have an online brochure website, a static web site will do. On the other hand, an online business that plans to list hundreds of products should opt for the dynamic option.
Dynamic websites are more expensive to implement because they require skilled professionals. While a graphics artist may be able to create a static website, they lack the programming skills required to implement such a solution. In addition, dynamic websites are less search engine friendly than static sites. Search engine spiders struggle to crawl through certain dynamic sites due to the often long and complicated URLs.
Real world example: URL's of dynamically generated sites often contain percentage signs (%), question marks (?), and other symbols such as &, + and $ or text such as cgi-bin. Although search engine spiders have become better at reading URL parameters (text after the question mark), but have a hard time when there are too many and therefore certain pages on dynamic sites with many URL parameters are not crawled.
Pros - Inexpensive development, Quick deployment, Low skill level required
Cons - Updates require html editing, Lack of interactivity, Stagnant content
Pros - Highly Scalable, Interactive, Updates don