Difference between a nerd and a geek

Nerds have the added distinction of being "unattractive".

Nerds are people of above-average intelligence who place little importance on their appearance. Nerds are often aware of their status, but they don't mind. In fact, many take pride in the putdown, as it means they're smart and not wrapped up in superficial worries.

Geek is a more specific term. Like nerds, geeks are smart, but they tend to focus more on technology.

These are the people you make fun of in school and later work for after school. So, to sum things up, if someone calls you a geek or a nerd, thank them.