What are flutes?
For thousands of years it has been known that an arch is the strongest way to span a given space. The inventors of corrugated cardboard applied this principle to paper, and put arches in the corrugated medium. These arches are known as flutes and as part of the finished cardboard, resist bending and pressure from all directions. Flutes come in several standard shapes and are designated by the letters A, B, C, E, and F.
