I'm very new to Arduino's and don't have much knowledge on hardware but I'm quite good at software.
I basically want to be able to simple turn on and off 3 different 12v applications individually using preferable only 1 Arduino! How would I be able to do this? It may be very simple but I don't even no where to start.
How much current does each one need?
A good Logic Level, Low Rds N-channel MOSFET can he used to connect - pin of the devices to GND.
Relays are good too for higher current, non-PWM situation where the switched line needs to be isolated from the Arduino power & Gnd, like switching 120VAC for a light, or high current for a motor that is not being sped up & down.