OSB Sheathing - Which side up or down?

Often times, builders will disagree on which side of OSB (oriented strand board) goes up/out or down/in. In this video, I will explain which way I installed my OSB on my animal barn and whether I will install it that way again.

Structurally, it does not matter which side of OSB goes up or down, according to Weyerhaeuser. There is a smooth side and a rough side, and the rough side is meant for safety purposes on floors and roofs.