While geek and nerd are often used interchangeably, there are subtle differences in connotation. A "geek" is typically seen as someone who is enthusiastic and deeply knowledgeable about a specific topic, while a "nerd" is more likely to be perceived as socially awkward or excessively intellectual. The distinction, however, is not always clear-cut, and both terms have become more fluid in their meanings over time.
# See - Geek Culture - Geeks, Nerds and Dorks