The tags which create hypertext links are important ones, but to talk about them, we need to briefly discuss how to specify document locations. Following that is a pathname. If the filename at the end is missing, index.html is assumed. Now that we know what URLs look like, we can use one to create a link. The quotes around the URL aren't usually necessary, but they're a good idea.
References can also be relative to the current document, as in the following examples.
A file in the same directory. A file in the parent directory. These links, if followed, bring you to the top of a document. You can name points within your document by using the following syntax. The name can be anything you want.