Corrugated fibreboard has two main components: the linerboard and the medium. Both are made from paper called containerboard. Linerboard is the flat facing that adheres to the medium. The medium is the wavy, fluted paper in between the liners.

There are four main types of corrugated board:
Single Face: One medium is glued to one liner. Typically used as a wrapping material.

Single Wall: The medium is between two liners. Also known as double face. The outside liner is smoother than the inside liner.

Double Wall: Three liners with two mediums in between. The outside medium is more compact than the inside medium. Used for heavy items which require increased protection and box rigidity.

Triple Wall: Four sheets of linerboard with the three mediums in between.

Flutes: The medium waves are called flutes. The direction and the distance between the flutes provides varying levels of stacking strength and/or cushioning. Generally, larger flute profiles deliver greater vertical compression strength and cushioning. Smaller flute profiles provide enhanced structural and graphics capabilities for retail packaging