1. Digital I/O Pins (2-13) - These pins can be used for both input and output. They are digital, which
means they can read and write two states: HIGH (usually 5V) or LOW (0V).
2. AREF (Analog Reference Pin)- This pin is used to set an external reference voltage (between 0 and 5V)
as the upper limit for the analog inputs.
3. Reset Button - Pressing this button restarts the program running on the Arduino.
4. Microcontroller - This is the main controller used for processing all the computation and control. It
runs your Arduino sketches.
5. Power LED Indicator - Lights up to show that the board is powered on.
6. TX and RX LEDs - These LEDs show the data transmission (TX) and reception (RX) on the USB interface,
useful for debugging communication.
7. Main Processor Reset Pin - A pin that, when connected to ground, will manually reset the processor.
8. USB Connection - Used for connecting the Arduino to a computer for programming and serial
communication.
9. DC Power Jack - Allows the Arduino to be powered from an external power supply instead of over
USB.
10. Voltage Regulator - Regulates the incoming voltage to a steady 5V which is used by the board.
11. ICSP Header - In-circuit Serial Programming header, used for programming the microcontroller
directly with a hardware programmer.
12. ATmega16U2 - Microcontroller used for USB to serial conversion, allowing the main processor to
communicate over USB.
13. USB to Serial Converter Chip - Facilitates the communication between the computer and the
microcontroller, allowing for program uploads and serial monitoring.
