DHT11 Digital Temperature and Humidity Sensor Module

The DHT11 is the entry-level environmental sensor most beginners meet first: a combined temperature and humidity sensor that outputs an already-digitized reading over a single data pin, so there is no analog-to-digital conversion or calibration curve to handle in code. That simplicity is the whole appeal, at the cost of accuracy - roughly plus or minus 2°C and 5% relative humidity - which is fine for a room thermometer or a classroom project and not fine for anything needing lab-grade precision.

It reads once per second at most, runs on 3.3V to 5.5V so it works on both 3.3V and 5V boards, and needs only three connections: power, ground and the single data line. Most Arduino and Raspberry Pi environmental sensor libraries support it directly.

Common uses are classroom and hobbyist weather stations, basic home automation temperature triggers, and any first project introducing digital sensor communication before moving on to more accurate sensors like the DHT22 or AHT10.