If you are looking for an user-friendly website which does not have any frequent updating, then this should be your pick. These are comparatively cheapest to develop and host. One of the disadvantages of this development is that it requires web development professional to update site.
If you are more focused on the management and functionality of the website, a dynamic site should be your first preference. This type of site provides the website owner the ability to update new contents to the site (text, images, videos etc.). The development and hosting of a dynamic site can be difficult and therefore these are a little expensive. Also if the site is not built by an experienced professional it can increase the loading time of the website. A frequent content update can benefit the SEO also.
A Content management system is a dynamic website which contains two sides, frontend and backend. The frontend is the portion visible to audience and backend is an interface used to update contents to the site. A CMS allows you to store pictures, documents and other files which can be retrieved and modified at any time by the website owner.
E-commerce website is also a kind of dynamic website which allows the website owner to update content according to their requirement. But the difference is, with an e-commerce website you could sell your products online and can allow financial transactions.