do i need some sort of chip between my arduino uno and the 12v water pump.?
Your topic was MOVED to its current forum category as it is more suitable than the original
The Arduino cannot supply enough voltage or current to drive a 12V water pump so you do need to use something as an interface between them and an external power supply to power the pump
The easiest to understand device would be a relay. This is a device that can turn a switch on and off under the control of the Arduino
Well a transistor at least, or a relay yes.
And if you need to change direction, an h-bridge.
If you want "simple", most "motor driver shields" will work to power a pump (assuming appropriate size. If you have a 12V@5A pump, you'll need a motor driver than supports greater than 5A.)
