A Molten Salt Reactor (MSR) is a type of nuclear reactor that uses liquid salt as both a coolant and a fuel solvent. This design allows for higher operating temperatures and improved thermal efficiency compared to traditional reactors. The molten salt can dissolve nuclear fuel, which can include various materials, making it versatile and potentially safer. MSRs are considered to have several safety advantages, such as a lower risk of meltdown due to the liquid state of the fuel. Additionally, they can operate at atmospheric pressure, reducing the risk of explosive failures. This technology is being explored for its potential in sustainable energy production.