Resistors

The most common component in any circuit — and the simplest.

A resistor limits how much current flows through part of a circuit, converting excess electrical energy into a small amount of heat. It has no polarity — it works the same no matter which way round you connect it.

Resistors are labelled by value in ohms, and small ones are often marked with colour bands instead of printed numbers — each colour stands for a digit, read left to right.

• Common values: 220Ω, 330Ω, 1kΩ, 10kΩ — kΩ means thousand ohms.
• A higher resistance value means less current gets through.
• Used to protect LEDs, set timing, divide voltage, and pull signal pins high or low.