At it’s fundamental level, a computer is basically just adding and subtracting binary numbers using a trick of computer wiring called digital logic, where you use configurations of circuits to represent basic math equations. All of the lowest-level code is written in binary instructions to these math gates, and the results are “interpreted” by us humans to represent math equations.
A binary question is a yes/no question that could be answered with the symbols:
- 1 = Yes, true, on, light.
- 0 = No, false, off, dark.
A lightbulb with two wires and a battery:
- Is on when the circuit is complete and lightbulb is lit.
- Is off when the circuit is broken (e.g. a switch is flipped “off”).
A lightbulb, two wires, a battery, and a switch:
- Negation: y = NOT(X) = -x (only has one input)
A lightbulb, many wires, a battery, and two switches in series:
- Conjuction: y = AND(x1,x2) = x1 AND x2 = x1 * x2
A lightbulb, many wires, a battery, and two switches in parallel:
- Disjuction: y = OR(X1, X2) = x1 OR x2 = x1 + x2
Binary truth table for and/or
- (x, y, AND, OR)
- (0, 0, 0, 0) both x and y are off, so AND and OR both produce off
- (1, 0, 0, 1) just x is on, y is off, so AND is off and OR is on
- (0, 1, 0, 1) just y is on, x is off this time, AND off, OR on
- (1, 1, 1, 1) x and y are both on, so AND and OR are on