Greenhouse

Greenhouse for growing strawberries

A greenhouse is an plant nursery enclosed in glass to keep in warm air. The heat comes from sunlight's infrared spectrum, which is used in the heat lamps that keep McDonald's french fries warm. Instead of blowing away, the air remains inside.

Many science writers have likened the earth's atmosphere to a greenhouse, an unfortunate analogy that obscures the way the atmosphere retains heat (see Greenhouse effect).