The M33 (Messier 33), also known as the Triangulum Galaxy, is a spiral galaxy located in the constellation Triangulum. It is the third-largest member of the Local Group of galaxies, after the Andromeda Galaxy (M31) and the Milky Way. M33 is approximately 2.73 million light-years away and has a diameter of about 60,000 light-years, making it smaller than the Milky Way. Known for its bright H II regions, such as NGC 604, it is an active star-forming galaxy. M33 is a popular target for astrophotographers and astronomers due to its proximity and rich structure.