Green House Effect
The green house effect describes the heat trapping by systems which are transparent for visible light but absorb infrared radiation.
In the earths atmosphere light from the sun reaches the ground and is converted into infrared radiation. The infrared is absorbed by so called green house gases like water vapor, carbon dioxide, methane, N2O, and others. The radiation is emitted again and might be absorbed and reemitted several times by other molecules or the surface before it is radiated into space.
The net energy flow of incoming sunlight and outgoing light and infrared radiation is zero. The higher the concentration of infrared trapping gases the higher the energy content in the atmosphere/earths surface and the higher their temperature.
In a green house light passes throu the windows, is converted into infrared radiation which is partially radiated back by the glass windows. The greenhouse effect on earth relys on the green house gases which are present in the whole atmosphere.