For instance, as I write on this wiki, I SmashWordsTogether to create an InlineLink. However, the MeatballLogo graphic floating above to your right (if you are graphics enabled), is an OutOfLineLink because it doesn't flow with the content.
In HTML, you typically wrap text in <A HREF="http://www.example.com">anchor tags</A> to create an InlineLink. [Of course, this wiki script will wrap the tags around any "h t t p : / /" string it finds for you.]