This document defines key vocabulary terms related to electrical circuits, components, and programming concepts for microcontrollers. It explains concepts like voltage, current, resistance, direct and alternating current, batteries, resistors, schematic diagrams, breadboards, embedded systems, microcontrollers, inputs, processing, outputs, digital and analog signals, pull-up/pull-down circuits, pin modes, if/else statements, pulse width modulation, time period, frequency, and duty cycle. It also defines components like resistors, potentiometers, and RGB LEDs.