What does the photo aspect ratio of 4:5 mean?

The aspect ratio of the photo is 4: 5, which means that the aspect ratio of the photo is 4: 5.

Specifically, if the width is 4 units, the height is 5 units.

In photography and image processing, aspect ratio is an important concept, which determines the aspect ratio of images. Common aspect ratios are 16: 9, 4: 3, 3: 2, etc. The aspect ratio of 4: 5 is a common ratio, which is often used for photo printing and exhibition.