The sun is actually the basis for almost every form of energy we use from wind to hydropower. But by "solar power" we typically mean use of the sun's rays to generate electricity through photovoltaic cells.
The photovoltaic (PV) cells or thin film circuits of the solar modules are specially manufactured to respond to light by producing electric current. The scientific term for " solar electricity " is " photovoltaic " energy - which means electricity from light. The more light the cells get the more electricity that can be produced. These cells when connected together, laminated and framed, are called a 'solar module' or sometimes 'PV (photovoltaic) modules'.
PV modules are usually installed on special ground or pole mounting structures. Modules may be mounted on rooftops provided that proper building and safety precautions are observed. For more output, modules are sometimes installed on a tracker - a mounting structure that moves to continually face the sun throughout the day.
Solar electricity can be used to run DC motors, or it may be stored in batteries for later use, or converted instantly into AC power and 'net metered' into the utility grid.