Generating Dynamic Pages for Tags

What does the "Generate dynamic pages for tags" option under Advanced SEO Features do?

This allows you to have access to creating tags on your blog posts and also access to dynamic pages, which are similar to blog categories but created automatically after creating a tag. Dynamic pages display all articles that are associated with the particular tag and behave just like category pages.

Dynamic pages are index pages that update with posts that have that tag associated. These dynamic pages can be accessed through the tags on the live version of the article.