Best Question Last Week At Work

Customer: Is Avatar in 3D here?
Manager: No. It's in 2D.
Customer: What's 2D?
Manager: 2D is a normal film.
Customer: Okay. So can I ask you something I've always wondered?
Manager: Sure.
Customer: If 3D is the glasses and 2D is normal, what's 1D?
Manager: /pause/ There is no 1D.

I really like the simplicity of that person's world view, I must say.
3D is the glasses, 2D is normal, and there's no 1D.
We've come a long way in film but not so much in the understanding of the basic sciences.

Though, as a co-worker pointed out later, since time could be considered a dimension unto itself we actually are showing Avatar in 3D with the time spent watching being the third dimension.