Amazing things! We design and place them on our networks!
They have multiple sensors such as humidity, FOG detectors, video traffic cctv, air quality sensors, anemometer (for wind speed/directions), rain etc.
They take allllll the data from the sensors and they feed into the motherboard or CPU. We take the raw data and make it readable to humans, package it in a file and transport it across TCP/IP network (THE INTERNET) and feed it into the met office or something like that!
I can post up a picture of one I designed if you like?