How Does Memory Foam Work?

Memory foam (temper foam) was originally developed by NASA in the 1960s to improve seat cushion safety in aircraft. It is made from polyurethane with additional chemicals that increase its viscosity and density. The key property is viscoelasticity: the foam responds to both pressure and temperature. Body heat softens the cells in the foam, allowing it to conform closely to your body contours and distribute weight evenly. When you move away, the foam slowly springs back to its original shape — the "memory" effect. The open-cell structure allows air to move through the material, though early versions retained heat, leading to modern gel-infused and open-cell designs for better cooling.