Spiral galaxies are a type of galaxy characterized by their spiral-shaped arms that wind outward from the center. They are among the most common types of galaxies in the universe and often contain a mix of young and old stars, along with gas and dust. The Milky Way is a well-known example of a spiral galaxy, showcasing a beautiful structure that is visible from Earth. These galaxies are classified into two main types: normal spirals and barred spirals. Normal spirals have arms that extend directly from the center, while barred spirals have a central bar-shaped structure from which the arms extend. Spiral galaxies play a crucial role in our understanding of the universe's structure and evolution.