A membership website will have specific content for members of the site. The content could be tutorials, videos, ebooks, digital downloads, news articles etc. Generally members have to pay a fee to become a member. It could be a one time fee or a recurring fee (billed per month/3 months/year etc) to get access to some or all of the members only content.
This is a powerful Membership Portal that can turn your existing users experience into a fully featured membership site.