Looking for practical Arduino projects? This guide shows how to control a relay from your smartphone using an Arduino Uno — ...

In this quick Arduino tutorial I will explain how you can control a relay using the Arduino Board, one 1K and one 10K resistors, 1 BC547 transistor, one 6V or 12V relay, one 1N4007 diode and a 12V fan ...

It has 250V / 5A Relays Outputs, 2A Digital Outputs, and Digital/Analog inputs and outputs, just like a regular Arduino, but everything is amped up.