It has the form of a slowly rotating, disk, with denser areas that look like the curved arms of a spiral. The Milky Way contains about 400 billion stars and is about 100,000 light years in diameter. They look like a burst from a fireworks shell when viewed through a large telescope. Globular clusters surround the main galaxy in the form of a halo. Galaxies are very large systems of stars, gas, etc. that often take a form of a slowly rotating disk, like our Milky Way.
Galaxies can also have a rounded look and some are more irregular in shape.
The closest major galaxy to our Milky Way galaxy is the Andromeda Galaxy. It is shaped much like our galaxy and is considered one third larger. This large system of stars and gas is 2.2 million light years away. There are billions of galaxies.