Was ist das Betamax?

I'm attending the 2003 Conference of the International Federation of Library Associations in Berlin. Buried in the welcome packet is this important tip:

VIDEOS
North American participants planning to use their video cameras in Germany should note that Betamax video cassettes are less easy to obtain in Germany, where VHS is the commonly used format.

Duly noted. My vintage-1982 two-piece Betamax camera and separate shoulder-mounted recording deck will be left at home.