A hat tip is a public acknowledgment to someone (or a website) for bringing something to the blogger's attention. Also known as H/T.
A group of people from a specifc location who interact in online communities using social media tools. They often, but not always, meet for a beer on a Friday evening.
Not the number of people that have visited your site. Hits actually refer to the number of items that make up that page. So two pictures, text and a graphic would be four items, or four hits.
Hyper Text Markup Language is the main language used for websites. It's written in short codes or tags surrounded by
< and > which give instructions as to how the word or image will appear: these words will be bold and these will not.