two character common cathode 7 segment display

I have a two character common cathode 7 segment display. How does it work? Sorry if this question seems a little basic, i'm an amateur. Thanks :)

Google is your friend:

http://www.tinkerhobby.com/arduino-2-digit-7-segment-display-counter/ http://www.tinkerhobby.com/arduino-2-digit-7-segment-display-counter-circuit/