What exactly is the Green House Effect?

-First Step is knowing the Sun gives out EM Radiation -Most of the Wavelengths can Pass through the Atmosphere, like IR -EM Radiation that has Short Wavelengths is Absorbed by the Earth - this Warms it Up -Then, the Earth Radiates some of that Heat that it Absorbed as Infrared Radiation -This is either Absorbed by the Greenhouse Gases, Transmitted into Space or is 'Bounced' back towards Earth -If its Absorbed and Bounced Back [Re-Emission] then it makes the Earth Warm. This is the Green House Effect