The term "geek" finds it origins in the 1500s, when it meant someone who was considered a fool. It is also thought to have come from the word "geckon", used in eighteenth century Austria-Hungary to refer to circus performers whose acts included biting the head off of a live chicken.
Looking at this chart, I think I would consider myself a pop culture, music geek, film geek, and gleek. I want to include a few others like tech, book, and food; but I feel like you have to be well-versed in a specific area to be considered a geek, whereas as I dapple. Also, the picture of the 'Dungeons and Dragons geek' cracked me up because I thought of Harris Trinsky with his Monster Manual from Freaks and Geeks (pictured center below). He was such a great character, haha. What kind of geek would you be?