The various incarnations of the Raspberry Pi have a wide scope of uses. They vary from things we know about, for example, as a desktop computer, a media device or a web server.
But there are many other unusual uses for them that we may not have heard about. For example, this Engadget article (https://www.engadget.com/raspberry-pi-ventilators-covid-19-163729140.html) talks about a RPi Zero being used to help save the lives of patients with COVID-19.