Is there a difference between a geek and a nerd?

Yes. Though the meanings of words change over time, my understanding is that a nerd is someone who is interested in and/or knowledgeable about academic subjects like science or history, whereas a geek is someone who is interested in things like comic books, computer games and tabletop games. There can be some crossover between the two though.

by Jennifer Muirhead

Although these terms may have been rooted in narrowly defined academic pursuits, I think they are now more widely used to refer to somebody who is by nature socially inept, unfashionalbe, clumsy and boring.

by Gayle Beveridge

This is something that has bothered me for a while! Sometimes the two words are used interchangeably and sometimes they seem to imply very different things.
I tend to associate nerds with science and geeks with computers but I notice in a previous question on here, "computer nerd" was used as a tag, so obviously not everyone agrees with me!

by VerityG

I have the same definition as Jennifer, but most people use them interchangeably.

by Bryony Harrison

I have never really given this any thought but i do not like either term.

by Gia

It seems that it is usually a put down from someone who is arrogant and narcissistic. I think some people use those terms incorrectly and I think that Nerds and Geeks are interesting people and simply show a greater passion and knowledge for things in general than the average person.

by brigi