110 is a miniature film format that comes in cartridges that include both spools. The frame size is 17mm x 13mm, making it roughly half the size of “half size” film and about one fourth the size of standard 135 film. It was introduced in 1972 and enjoyed significant popularity for a few years with many different film choices available from multiple manufacturers. Most 110 cameras were very simple point and shoot models or toy cameras. I remember getting one for free by mailing in the coupon on a cereal box when I was a kid. It came with the film included and I enjoyed taking photos with my very own camera, but when my dad found out how much it was going to cost to develop the film he wouldn’t let me and I was heartbroken.
I have one 110 camera, the Pentax Auto 110.