Here's why:

* Different speeds: Light travels at different speeds in different materials. For example, light travels faster in air than in water.

* Change in direction: When light passes from one medium to another, its speed changes, causing it to change direction. This change in direction is called refraction.

* Angle of incidence and angle of refraction: The amount of bending depends on the angle at which the light strikes the interface (angle of incidence) and the refractive indices of the two media.

Let me know if you'd like a more detailed explanation of the factors affecting refraction!