There are many different kinds of websites out there. If you are looking to build a site to make money or just for fun then you will have a lot to choose from.
The first site is a statistic site. This is a site that you just have to set up once and fill it with evergreen content. Ecommerce stores would also fall into a statistic site because you can keep the same products on your site forever.
A blog is the second kind of site. The blogging phenomenon has brought a lot more people to write online. Here you write posts about your feelings and beliefs. Other people who like what you write can follow you and get emailed every time you write a new post. If you write a good blog you can make a lot of money with it.
A third site is a web 2.0 site. This can be things like forums or article directories. They are harder to get off the ground and to get people to actually use them. But they can grow pretty fast once they are.