Assemblies of photovoltaic cells are used to make solar modules, which generate electrical power from sunlight.
Multiple cells in an integrated group, all oriented in one plane, constitute a "solar photovoltaic panel" or a "solar photovoltaic module," as distinguished from a "solar thermal module" or a “solar hot water panel. The electrical energy generated from solar modules, comonly referred to as solar power, is an example of solar energy. A group of connected solar modules is called an "array."
The most prevalent bulk material for solar cells is crystalline silicon (c-Si).
Source: Wikipedia; Solar Cell, April 4th, 2014 (http://en.wikipedia.org/wiki/Solar_cell)