What are the four main types of ramen broth?

The four primary types of ramen broth are Shio (salt), Shoyu (soy sauce), Miso (fermented bean paste), and Tonkotsu (pork bone). Shio is the lightest and clearest of the four, seasoned with salt and often made with a chicken or seafood-based dashi. Shoyu is also a clear broth, but it's seasoned with soy sauce, giving it a brown color and a more complex, savory flavor. Miso broth is made by dissolving miso paste into a stock, resulting in a rich, opaque, and deeply flavorful soup. Tonkotsu is a rich and creamy broth made by boiling pork bones for many hours, which releases collagen and fat, creating a milky, opaque appearance and a deep, savory flavor.