Reflection is what happens when light, sound, or heat bounces off a surface instead of passing through it. When you look in a mirror, you see your reflection because light rays hit the mirror's smooth surface and bounce back to your eyes. Still water creates beautiful reflections of trees and clouds for the same reason.

Different surfaces reflect differently. A mirror gives a clear, sharp reflection because its surface is so smooth and flat. A lake might give a wavy, distorted reflection if the wind ripples the water. Dark or rough surfaces absorb more light and reflect less, which is why you can't see your reflection in a chalkboard.

The word also means careful thinking about something that happened. When your teacher asks you to write a reflection on a field trip, she wants you to think deeply about what you learned and experienced. You might reflect on a mistake to understand what went wrong, or reflect on a success to figure out what you did right. This kind of reflection helps you learn and grow from your experiences.

Both meanings share the idea of something coming back to you: light bouncing back to show you an image, or your thoughts returning as you examine an experience.