Memory Foam - Commonly referred to Visco-elastic or Swedish foam. This foam was originally developed in the early 1970's at NASA's Ames Research Center in an effort to relieve astronauts as means to absorb the incredible G-force during take off and reentry. Visco-elastic memory foam is made up of billions of high density, Visco-elastic memory cells that are temperature and body weight sensitive. Memory Foam adjusts to the contours of your body by softening in warm areas and remaining firm in cooler areas. Since it offers no resistance, there is less pressure on your body and provides even and comfortable support throughout your body, allowing longer, deeper and more restorative sleep.