Definition: digital circuit

An electronic circuit that processes binary data according to the rules of Boolean logic (AND, OR and NOT). Officially an "integrated circuit," for the history of this world-changing discovery, see integrated circuit. See chip and Bebop to the Boolean Boogie.

Digital Plumbing!
A digital circuit can be conceptualized as a mass of plumbing with water instead of electricity. A transistor is a valve (open/close). A resistor constrains the water into a smaller pipe. A capacitor is a tank, and a diode ensures water flows in one direction.

Now imagine water passing through one valve that reaches a second valve, causing it to open and allowing water from a third valve to flow through that reaches a fourth valve, and so on.

From Logic to Plumbing

The plumbing diagram above depicts a circuit known as a "half-adder," which adds one bit to another in every computer. To understand this at a gut level, look up half-adder and trace the path yourself with paper and pencil.