ITT: How do Japanese Multiply (NOT A REPRODUCTION TOPIC)

This is the exact same as regular, digit-by-digit multiplication, except drawn with lines instead of numbers in a way that makes it look unique.

Notice the video only uses 1s, 2s, and 3s. Attempting this method with higher numbers would illustrate why we memorize multiplication tables so that we don't have to use this method. This is a primitive form of the same thing you do on a daily basis.