Arduino Reference [updated] May 2026

The Official Arduino Reference categorizes functions to help you interact with the hardware effortlessly. :

: Sends data to the Serial Monitor for debugging or viewing sensor data. Understanding Data Types and Variables

: Reads the state of a pin (either HIGH or LOW ). Analog I/O : arduino reference

: This function runs exactly once when the board powers up or resets. It is where you initialize pin modes (setting them as inputs or outputs) and start serial communication.

: Sends a HIGH (5V or 3.3V) or LOW (0V) signal to a digital pin. The Official Arduino Reference categorizes functions to help

Choosing the right data type ensures your code runs efficiently on microcontrollers with limited memory, like the ATmega328P found on the Arduino Uno. Description boolean Stores true or false (often interchangeable with HIGH / LOW ). int Standard integer for numbers. long Extended size for large numbers up to ~2.1 billion. float For numbers with decimal points. char Stores a single character.

: Converts an incoming analog voltage into a digital value between 0 and 1023. Analog I/O : : This function runs exactly

: Uses Pulse Width Modulation (PWM) to simulate an analog output. Note that on some boards like the ESP32, this may require specific libraries or different syntax . Communication :