Skylight is defined as a special type of opening provided in the roof of the building, which is covered with translucent or transparent material to allow natural light to come into the house directly during daytime. Depending of the materials, type of use, types of roof and room type there are more types of skylights. Here are the most used:
Dome acrylic skylight
Barrel vault skylight
More about each of them, in the link bellow.