Galaxies come in several shapes and forms, including spiral galaxies which make up 60% of galaxies and have spiral arms radiating from a central bulge, barred spiral galaxies which have a bar through the center, and elliptical galaxies which are elliptically shaped. Our galaxy, the Milky Way, is a barred spiral galaxy over 100,000 light years in diameter that rotates clockwise and contains a massive black hole at its center.