What is "memory foam"

n. foam consisting of polyurethane and other chemicals used in the manufacturing of pillows, mattress, laptop sleeves, etc, which reacts to body heat and molds to the shape of the body.

Memory foam is polyurethane with additional chemicals increasing its viscosity and density. It is often referred to as " viscoelastic" polyurethane foam, or low-resilience polyurethane foam (see LRPu). Higher-density memory foam softens in reaction to body heat, allowing it to mold to a warm body in a few minutes. Faster speed of recovery of a foam to its original shape after a weight is removed is sometimes claimed as an advantage by memory-foam mattress producers, who may talk of "newer generation" foams with "faster recovery."