Light that is visible to the human eye is a tiny slice of the light (electro magnetic waves) which we know exists. Some of the other frequencies of light can "shine" through steel. Gamma waves can shine through damn bear anything. Then of course there are the neutrinos which can shine through planets or even stars.

An interesting fact is that you can make light move at different speeds depending upon the material you shine the light through.
It slows down in glass and shows its changes in refracted light. It slows even more in diamond and refracts at even greter angles.
In super cooled fields of gas, light has been made to virtually stop.