1:1 Square format is the ratio for some medium format cameras. It’s also compatible with social media sites such as Instagram and Facebook.
3:2 Full frame DSLRs and APS-C crop sensor cameras have 3:2 sensors.
4:3 Smartphones and Micro Four Thirds cameras shoot in a 4:3 aspect ratio.
16:9 Used for high definition video, widescreen format is the standard for HDTV.