why do they call it greenhouse effect?

So my last blog was mainly about global warming and how I had no idea what it was and things of that nature well this blog.. I did a little bit of research and found out some facts about global warming that I didn't know before. Here we go.....
Global warming is best known as the "greenhouse effect", what that means is that the natural system that keeps Earth warm enough to sustain life--this is a good thing. But an abundance of greenhouse gases emitted into the atmosphere has been collecting in the atmosphere and effectively forming an additional heat blanket around the Earth. In other words, human activities are intensifying the greenhouse effect and moving the Earth's temperature to dangerous levels. This is a good thing but like stated before, too many greenhouse gases aren't good.
The main things that cause the "greenhouse effect" are; Actually humans. We cause the greenhouse effect by polluting, and contaminating are oceans, and not recyling. We also cause the green house effect by processing so many different chemicals that are then release into the air. The greenhouse effect is actually beneficial to the Earth. It is only when human-made processes increase its speed that the problems occur. One main problem is the oft repeated 'Global Warming'. One of the man-made causes of the Green House effect is deforestation. Deforestation increases the amount of carbon-di-oxide in the atmosphere. Also, due to the disappearance of trees, photosythesis cannot take place. Deforestation causes of the greenhouse effect. Deforestation is rampant today due to the increase in human civilisation.