•The most common type of re-entry protection is a thermal protection system (TPS) of some kind, but there is also a new inflatable re-entry system in development. •The most common is the “Ablative” type heat shield. It works by creating a protective layer from re-entry friction plasma by burning materials in the heat shield to create a gaseous boundary layer. This is called blockage. •Most Ablative heat shields are made mostly from carbon-phenolic which chars, melts and sublimes at high friction within the Atmosphere.