What is kiosk?

How kiosk mode looks? Why people emphasize on kiosk mode so much?

Launch any URL as a full-screen kiosk. Basic kiosk application. Allows any URL to be loaded as a fullscreen kiosk in Google Chrome or Chrome OS, also disables device sleep mode while app is running. Additional interface, administration, and scheduling options are also provided. people mostly use chromebit kiosk mode because it is easy and simple to do.