A man is washing windows on the 25th floor of an apartment building. Suddenly, he slips and falls. He has nothing to cushion his fall, and no safety equipment—but he doesn't get hurt. How is this possible?

He is washing the inside of the windows.

This is a classic riddle and the answer lies in a play on words. The man doesn't get hurt because he is washing the windows on the outside of the 25th floor, meaning he is already outside the building. This implies that he is washing the windows of the outside of the building, not the inside. Therefore, the man doesn't fall to the ground because he was never inside the building to begin with.