There are all kinds of geeks, nerds, spazzes, and dorks out there. Each of them have one thing in common: they are obsessed with something. One thing. They are just plain bonkers over it!
Either way, geeks can and do come in all shapes and sizes and from all walks of life. The idea and stereotype of a geek has changed dramatically and drastically as time goes on, partially due to the improved public awareness but mainly owing to the rise of video games and technology as “a cool thing”.
Here is a flow chart from Flowtown explaining geeks and how they came to be (click to see larger size):