During a panel at Big Apple Comic-Con, Brent Spiner explained to the audience precisely how the British pronunciation of his Star Trek: The Next Generation character name Data started, throwing in a rather perfect impression of actor Patrick Stewart to make his point. This funny scenario also lead way to a new rule on set.
…he [Gene Roddenberry] said well I’m gonna make a new rule right here. Whoever says the name first, that’s what they’re going to be called. the way it went the entire series.
Spiner also added that his character changed the way Americans pronounce the word as well.
it was always data [dah-ta] and data [day-ta] but I think in America data [dah-ta] was much more common and now data [day-ta] is much more common thanks to Patrick Stewart and moi.
via Boing Boing