Memory foam was developed by NASA in 1966 to improve the shock absorption of aircraft cushions. The temperature-sensitive memory foam was initially referred to as "slow spring back foam” because the solid open-cell solid structure matches pressure against it, yet slowly spring back to its original shape. However, it wasn’t until the 1990’s, when Fagerdella World Foams released their flagship TempurPedic Swedish mattress, that memory foam was introduced as a mattress material.
Memory foam has an open-cell structure that reacts to heat and weight. Once pressure is removed, memory foam slowly returns to its original shape. When memory foam is used as a mattress material this quality helps the mattress evenly cushion the body, creating a pressure free, contouring feel as the mattress adapts to the impact of your body and re-forms around your curves.
When you lie on a visco-elastic memory foam bed or memory foam mattress topper, the molecules that comprise the viscous material are compressed and rearranged. The rate and amount of contouring created by the rearrangement of the viscous cells is determined by the density of the viscous material and your body’s temperature, shape and weight. Once your body heat and the applied pressure are absorbed, the cells soften. This is what causes the memory foam mattress to contour and conform to your body shape. No other bedding works or feels quite like this.