The DHT22 Sensor Module is a basic, low-cost digital  temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air and spits out a digital signal on the data pin (no analog input pins are needed). It's fairly simple to use but requires careful timing to grab data. The only real downside of this sensor is you can only get new data from it once every 2 seconds, so when using our library, sensor readings can be up to 2 seconds old.

Simply connect the first pin on the left to 3-5v power, the second pin to your data input pin, and the rightmost pin to the ground. Although it uses a single wire to send data it is not Dallas One wire compatible if you want multiple sensors, each one must have its own data pin feature & application: High precision capacitive type full range temperature compensated relative humidity and temperature measurement calibrated digital signal outstanding long-term stability extra components not needed long transmission distance low power consumption 4 pins packaged and fully interchangeable.