Arduino Starter Kit (Absolute Beginner)

Jargon buster

Plain-language definitions for the technical terms used above.

encoder

An encoder is a sensor that converts the rotation or position of a shaft, knob or dial into electrical signals, reporting movement as incremental steps and direction, or as an absolute position. It is used to track how far something has turned, which matters for precise positioning, speed control, repeatable movement, or using a rotary knob as an input.

LED

A light-emitting diode (LED) is a small electronic component that emits light when current flows through it in the correct direction. Because it only conducts one way, its polarity matters, and a through-hole LED must be soldered the correct way around to light up.

photocell

A light-sensitive component whose electrical resistance changes with the amount of light falling on it. It matters when choosing or using light sensors, automatic lights, or brightness-detecting circuits because its response speed, resistance range, and sensitivity affect how reliably it detects light levels.

PIR sensor

A passive infrared sensor detects changes in heat, usually from a person moving across its view. It matters because PIR sensors are common for lights and alarms, but they can miss people who are present but not moving much.

servo

A servo is a motor with built-in position control, usually told to move to a specific angle by a control signal. It matters when you need repeatable movement, such as steering, arms, flaps, or linkages, rather than continuous spinning.