My first cutting board was made of thick white polytherine or plastic, idk? It came with block knives set from Wal-Mart. Now it's all dirty/germy in groves where knife cut it, I haven't used it for last 5 yrs. My current cutting board started out its life as a Cosco cheese assortment plate, cheese was already pre-cut. It's made of thin black plastic tray with low side walls that keeps cut food in place, it doesn't roll of the board onto the table or floor, which is always great! I have been using it for last 5 yrs.