How does the concept of slow down light impact the speed of light in a medium?

The concept of slowing down light refers to the phenomenon where light travels at a reduced speed when passing through a medium, such as glass or water. This is due to interactions between the light and the atoms in the medium, which can cause the light to be absorbed and re-emitted multiple times. As a result, the speed of light in the medium is slower than its speed in a vacuum.