Component Glossary

Arduino

The Arduino is a small computer that runs your program and controls all connected components.

Pins

Pins are pieces of metal are connected to an electrical component.

Types of Pins (Important)

Input pins listen for information from sensors or buttons

Output pins send instructions to lights, motors, or displays

Power pins supply electricity and do not send information

• Digital Pins (0–13):
• Can be input (buttons, sensors) or output (LEDs, buzzers)
• Analog Pins (A0–A5):
• Used as input to read changing values like light or temperature
• 5V / 3.3V: Power
• GND: Ground (return path for electricity)

Breadboard

A breadboard lets you build circuits without soldering.

Holes

Holes are connected internally in rows and columns

Side rails are commonly used for power and ground

Resistor

A resistor is a small component that limits how much electricity can flow through a circuit.

Pins

• It does not matter which side you plug a resistor into.

Jumper Wires

Used to connect components together.

Types

• Male to Male: Arduino to breadboard
• Male to Female: Arduino to sensor
• Female to Female: Sensor to sensor

Bluetooth Module

Allows wireless communication with a phone or computer.

Pins

• TX (Output): Sends data from the module
• RX (Input): Receives data from Arduino
• VCC: Power
• GND: Ground

Digital Display (TM1637)

Shows numbers such as timers or counters.

Pins

• CLK (Input): Clock signal from Arduino
• DIO (Input): Data from Arduino
• VCC: Power
• GND: Ground

RGB LED Light Strip (FastLED)

A strip of LEDs where each light can show a different color.

Pins

• DATA (Input) (Green): Color instructions from Arduino
• 5V (Red): Power
• GND (White or Black): Ground

LCD Screen (I2C)

Displays text using only two data wires.

Pins

• SDA (Input): Data from Arduino
• SCL (Input): Clock from Arduino
• VCC: Power
• GND: Ground

LED

A single light. (Light Emitting Diode). It only allows electricity to flow in one direction.

Pins

• The long pin or wire connected to the LED. Used to turn the led on.
• GND (Ground) The short wire connected to the pin.

LED Matrix (MAX7219)

A grid of LEDs used to draw.

Pins

• DIN (Input): Data from Arduino
• CLK (Input): Clock
• CS (Input): Chip select
• VCC: Power
• GND: Ground

Motor (L298 Driver)

Controls DC motors safely.

Pins

• IN1 / IN2 (Input): Direction control
• ENA (Input): Speed control
• Motor Outputs: Connect to motor
• Power / GND: Motor power

Passive Buzzer

Makes sound when controlled by Arduino.

Pins

• Signal (Input): Sound control (Find the + icon circled in red)
• GND: Ground

RGB LED

A single LED that can display many colors.

Pins

• R (Input): Red control
• G (Input): Green control
• B (Input): Blue control
• Common: Power or Ground

Servo Motor

Moves to a specific angle.

Pins

• Signal (Input): Angle control (Orange or Yellow)
• Power: (Red)
• GND: (Brown)

Stepper Motor

Moves in precise steps.

Pins

• Multiple input pins connect to a driver
• Driver connects to Arduino output pins
• Separate power for the motor

Analog Sensor (General)

Returns a range of values, not just on or off.

Pins

• Signal (Output): Sends value to Arduino
• VCC: Power
• GND: Ground

Photo Resistor (Light Sensor)

Detects how bright the environment is.

Pins

• Two legs used with a resistor
• Output goes to an analog input

Potentiometer

Pins

• Middle (Output): Value to Arduino
• Side Pins: Power and Ground

Push Button

Detects when it is pressed.

Pins

• One pin goes to ground
• The other goes to a pin on the arduino.

Touch Sensor

Detects when touched.

Pins

• Signal (Output): Touch detected
• VCC: Power
• GND: Ground

IR Motion Sensor

Detects movement.

Pins

• OUT (Output): Motion detected
• VCC: Power
• GND: Ground

IR Remote Receiver

Receives commands from a remote.

Pins

• Signal (Output): Button data
• VCC: Power
• GND: Ground

Joystick

Used for directional control.

Pins

• AX (Output): Left / Right
• AY (Output): Up / Down
• SW (Output): Button press
• VCC: Power
• GND: Ground

Ultrasonic Sensor

Measures distance using sound.

Pins

• Trig (Input): Arduino sends sound
• Echo (Output): Distance signal
• VCC: Power
• GND: Ground

RFID (RDM630)

Reads RFID cards or key fobs.

RFID Fob Example

Pins

Look at the electroblock

• TX (Output): Tag number
• VCC: Power
• GND: Ground

Temperature Sensor (DHT)

Measures temperature and humidity.

Pins

• Data (Output): Sensor readings
• VCC: Power
• GND: Ground

Thermistor (Standard)

Measures temperature using resistance.

Pins

• Two legs used in a voltage divider
• Output read by an analog input