Doors Lyrics Follow

A door is a moving mechanism used to block off and allow access to, an entrance to or within an enclosed space, such as a building, room or vehicle. Doors normally consist of one or two solid panels, with or without windows, that swing using hinges horizontally. These hinges are attached to the door's edge but there are also doors that slide, fold or spin. The main purpose of a door is to control physical access.
Doors are significant in preventing the spread of fire and as a barrier to noise. Many doors are equipped with locking mechanisms to allow entrance to certain people and keep out others.
When opened, doors can allow people, animals, ventilation or light to pass through. The door is used to control the physical atmosphere within a space by enclosing the air drafts, so that interiors may be more effectively heated or cooled. When closed, a door normally impedes the transfer of air from one side to the other. Similar structures that do allow air to be transferred through some form of a grillwork are called gates.
Doors may have an aesthetic purpose in creating an impression of what lies beyond; for example, keeping administrative and factory areas of a building separate. In less formal settings, doors may also be seen as a sign of the desire for privacy. As a form of courtesy and civility, people often knock before opening a door and entering a room. Some doors even have designated "knockers." like the one in the photo located next to this text.
Doors are often symbolically endowed with ritualistic purposes. For example, being granted access to a door, including the guarding or receiving of the key to that door, may have special significance. Similarly, doors and doorways frequently appear in literature and the arts in metaphorical or allegorical context, often as a portent of change.
In most cases the interior side of a door matches its exterior side but, in some other cases, there are sharp contrasts between the two sides, such as in the case of a vehicle door.

Source: Wikipedia