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Binary, a system of expressing numbers using only two discrete symbols (typically: 1, and 0), is the system used by modern digital computers for simple numeric quantities. It was Claude Shannon who made the connection between George Boole's work on logical systems based on true and false values and using electronic circuits to implement them as circuitry. Using a binary system makes a physical implementation much simpler than a decimal system such as Charles Babbage's Difference Engine.

Counting in binary (performance)

File:Hc2012 binary.160p.webm

Rules (Binary):
1. When tapped on your shoulder, raise your hand.
2. When you get tapped and your hand is raised, tap the shoulder of the person next to you put your hand down.