AM2301 Capacitive Digital Temperature & Humidity Sensor sensor is one of the commonest from the range of DHT temperature sensors; and boasts a relatively high-temperature measurement accuracy of 0.5°C in 0.1°C steps with a relative humidity accuracy of ± 3%.
It has only 3 wires, including power and ground, meaning only one digital pin is required to interface it to a microcontroller. For Arduino development platforms the sensor is very well supported by the DHT library available from the Arduino Playground website.
Example Arduino Sketch, Library, and Datasheet available on our support forum here.
Note: This package does not include the Arduino board.