How big is the ordinary photo?

(R stands for) R stands for Rectangle (English is rectangle), calculated with the shortest side. 3X4 inch -3R is generally called 4 inch 75MM X 102MM 4X6 inch -4R is generally called 6 inch; 102MM X 152MM5X7 inch -5r, commonly known as 7 inch; 140MM X 200MM 6X8 inches -6r, commonly known as 8 inches; 160MM X 200MM 7X 10 inch -7r, commonly known as 10 inch; 8X 10 inch-this is the kind of 20x24cm that is often needed in movies and games; 200MM X 240MM 10X 12 inch-also a common size; 1 1X 14 inch-mostly the size of a photo studio album; 12X 16 inch-general 135 negative magnification size, complete composition; 300 mm X 360MM 4R and 4D are terms of photo size. The so-called 4R is what we usually call a 6-inch photo. The actual size is 10.2cmX 15.2cm (or 15.2cm× 10.2cm), and the aspect ratio is 3: 2 (or 2: 3).