How Does a Fish Know Which Way to Swim?

Imagine being in a dark room with no lights on. You can still feel where the walls are, even if you can't see them. Fish do something similar, they use special senses to figure out where they are and which way to swim.

Like a compass in their head, fish have a sense called lateral line. It helps them feel vibrations in the water around them, like ripples or other fish moving nearby. They also have eyes that let them see light and shadows. Together, these senses help fish know where they are, kind of like having a map inside their body.