interactive and browsable pdf

In my head, all PDFs are browsable (you can look at them in a browser). Some are interactive too, but different people mean different things. For example, for some that means having links inside the document. For others, pop-up videos and merry music. 
What do you mean, specifically, by interactive and browsable? Perhsps you've found a great PDF and want to make one like that...? If so, please share a link to that PDF (not just a link to a site with PDFs, that will probably be blocked as spam).