Catalogue

The same ATmega328P as the Uno in a package that drops into a breadboard, which is what you want once a project stops being an experiment and starts being a thing that has to live in a box. Two things worth knowing before you order: A6 and A7 are analog-input only and cannot be used as digital pins, and the USB connector varies by batch — mini-B, micro or USB-C. Ask before ordering if the connector matters to you.

The board most people start on, and the one most Kenyan workshops keep a drawer of. An ATmega328P at 16 MHz, 14 digital I/O and 6 analog inputs, powered over USB-B or a barrel jack. Shields stack straight onto it, which is why it stays in service long after you have outgrown it. Stock here is Arduino-compatible rather than Italian-made, so the USB-serial chip is usually a CH340 — on Windows you may need the CH340 driver before the port shows up. If uploads fail with an avrdude sync error, try Tools > Processor > ATmega328P (Old Bootloader).