M-Type Main Sequence Stars are the coolest and smallest stars on the main sequence of the Hertzsprung-Russell diagram. They have surface temperatures ranging from about 2,400 to 3,700 Kelvin and are often red in color. These stars are also known as red dwarfs and make up the majority of stars in the universe. Due to their low mass, M-type stars burn their hydrogen fuel very slowly, allowing them to have long lifespans, often lasting tens to hundreds of billions of years. This slow burning process means they are stable and can remain in the main sequence phase for a significant portion of their lives.