DHT22 is a small temperature and humidity sensor, easy to use. We can use a Raspberry Pi to communicate with it, and make graphs of temperature and humidity evolution. Material We need: a Raspberry Pi (here the 3B+ version) a good quality SD card (class 10) a power supply for the Raspberry (5V between 2.5A and 3A) the DHT22 sensor a 10 kΩ resistor a breadboard another computer to connect to the RPi using SSH an RJ45 cable RPi installation SD card preparation The easiest way to install the RPi OS is to use the Raspberry Pi Imager software, which allows you to choose the right version of the OS, download it and install it on the SD card.