A conservatory, more modernly known as a greenhouse, is a glass and metal building where tropical flowers and plants can be grown in a protected and controlled environment. They can be an addition to a home or a free-standing structure.

There are public conservatories where people can go to enjoy and appreciate the garden greenery. They became popular during the nineteenth century and were found in the colder climate cities. People began to hold social gatherings, such as tea parties, in these conservatories near the end of the century.

Garden conservatories are small and generally used as an extra room on a home, instead of the whole area being dedicated to plants and flowers. This kind of conservatory became prominent in the mid-twentieth century and is also referred to as a sunroom. They became popular as people wanted to enjoy the natural beauty of the landscape, while at the same time being protected from the elements.

The materials used to construct modern conservatories have greatly improved as technology has improved. Plastics and wood can be substituted for glass and metal, in some cases. The glass, now tempered, has improved the efficiency, and the roof can be made of glass, a durable plastic which allows light to penetrate, or even shingle. Now the sunroom addition to a home is no longer restricted to the colder climates, and people in warm climates can enjoy the open space that a conservatory allows.

In urban areas privacy became an issue for the homeowners. European companies saw this need and were the first to design window coverings to custom fit the windows in the conservatories without endangering the strength of the framework. This quickly became a very profitable venture. Homeowners today are able to adjust the blinds via a hand-held remote without leaving the comfort of their chair.

Seventeenth century England had the earliest known conservatories, but they would not be recognized as such today. They were simple stone buildings with the conservatory room having more glazing than the rest of the dwelling. Their primary use was scientific as plants and seeds were gathered from warmer areas in Europe, South America, and Australia. The climate in England would not do for these more tropical specimens, thus the idea of the conservatory came about.

Today, one can find a public conservatory almost anywhere in the world. Some have been around for centuries, while others are relatively modern. The Royal Greenhouses of Laeken located in Brussels has a total floor space of 270,000 square feet, and is only open to the public for a short two week period in April-May when the flowers are in full bloom. The Muttart Conservatory in Canada has four glass pyramid-shaped conservatories that is open year round. London has the Kew Gardens which has the largest collection of living plants, and in 2009 celebrated their 250th anniversary. Part of the Belfast Botanic Gardens in Ireland is the Palm House. The Palm House is notable because it is one of the first types of curvilinear cast iron glass houses in the world. The United States has many conservatories spread across much of the country.