Speed cells are like little GPS trackers in our brain that help us move fast. Imagine you are playing tag with your friends in a big field. You need to know where your friends are to tag them! Your brain sends signals to your eyes so you can see where your friends are and then it sends signals to your feet so you can run after them.
Speed cells work the same way in your brain. They help you know where you are in your environment so you can move quickly and smoothly. If you are running through a park, your speed cells tell your brain how fast you are going and help you change direction without bumping into anything.
These cells are really important for animals that need to move quickly to catch their food or run away from danger. Scientists have discovered that speed cells are found in a part of the brain called the hippocampus, which is also important for things like memory and navigation.