Anyone can geek out to their favorite absofab stuff: RPG, manga, marching band and choir, porn, horticulture, coding languages, magical arcana, sci-fi, guitars, jazz recordings, baseball stats...whatever. But nerdiness is a character trait, a way of living and being in the world. It's how you relate to the stuff you love and are driven to do, to the exclusion of what's popular or expected.
I am a nerd. Have been since I was a girl. The tides have turned in the last 10-15 years. Nerds are glossy and hypervisible, en vogue now. We can all laugh and nod at Big Bang Theory together. But real nerds are always prepared for the tides to turn again. #nerdsabide