A bunch of people gather arround a big table with rulebooks and dices. There's a gamemaster who describes the rules and throws the dice for different reasons.
It's like <img src="/ubbthreads/images/graemlins/div.gif" alt="" /> without a computer. The graphics depend on your brain <img src="/ubbthreads/images/graemlins/winkwink.gif" alt="" />.