IR receivers are little diodes with a photocell that are tuned to detect to infrared light. They are usually used for remote control detection - every TV and DVD player has one of these in the front to listen for the IR signal from the clicker.
To use, connect pin 3 (all the way to the right) to 5V power, pin 2 (middle) to ground and listen on pin 1. It doesn't do any decoding of the signal, just passes the 'raw data' along.
- IR Remote Control Receiver
- Wide operating voltage range: 2.7V to 5.5VDC
- Built-in Filter at 38KHz
- Simple interface
- Compatible with Arduino, Raspberry Pi
For IR receiver datasheet, please click here
For nice explanation of IR remote signal basics, click here