Another name for this is chipwood. A light cardboard type of paper often used for cereal boxes and school supplies.

A paper product with a grammage that is higher than paper, but lower than cardboard. A distinction is made between single-layer and multilayer board. In the U.S., paperboard is often called “cover paper”.

Monolayer paperboard is basically thicker paper, frequently used in multilayers.

a cardboard suitable for making posters

A stiff cardboard composed of layers of paper, or paper pulp, compressed into a sheet.

The distinction between paper and paperboard is not sharp, but broadly speaking, the thicker (over 0.012 inch), heavier, and more rigid grades of paper are called paperboard.

Paperboard, within the commercial papermaking industry, is simply the term used to describe a thick sheet of paper. Because of this simple definition, there is some confusion in the industry as to what qualifies as paperboard. The term is not familiar to many English speakers, who use the broader non-technical term cardboard instead.