Barry is the more obvious nerd...not only his fascination with science, but he was the ultimate comics fanboy/collector, with a meticulously organized collection that made you sometimes wonder if he had OCD.
Wally idolized the Flash (Barry), but never came across a particularly nerdy or geeky. I don't think Wally collected comics, and could be sloppy (especially in the pre-Waid era) in a way that Barry wouldn't be comfortable with.
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