All the methods? Seriously... I'm sure there are many if you allow for all the wysiwyg tools that will use a slightly different mechanism. How about you tell us what you are trying to do and then we might be able to tell you what you actually want to know.
Hyperlinks in HTML are fairly simple. Here is a very basic example: <a href="http:// URL LINK GOES HERE">Text or graphic that will become the hyperlink.</a> For more in depth knowledge, a quick Google search will help you.