It's loaded with sensors for air and weather, colour and light, and sound, and slots right onto your micro:bit. Just slot in your micro:bit, then code enviro:bit with the block-based Microsoft MakeCode editor, or with MicroPython in the Mu code editor. The sensors go hand-in-hand really well with the LED matrix on micro:bit, letting you graph sensors readings or have the LEDs react to sound, for example.
