Balcony a platform projecting from the wall of a building, supported by column

Column

A column or pillar in architecture and structural engineering is a vertical structural element that transmits, through compression, the weight of the structure above to other structural elements below. For the purpose of wind or earthquake engineering, columns may be designed to resist lateral forces...

s or console

Corbel

In architecture a corbel is a piece of stone jutting out of a wall to carry any superincumbent weight. A piece of timber projecting in the same way was called a "tassel" or a "bragger". The technique of corbelling, where rows of corbels deeply keyed inside a wall support a projecting wall or...

 brackets, and enclosed with a balustrade.
The traditional Maltese

Malta

Malta , officially known as the Republic of Malta , is a Southern European country consisting of an archipelago situated in the centre of the Mediterranean, south of Sicily, east of Tunisia and north of Libya, with Gibraltar to the west and Alexandria to the east.Malta covers just over in...

 balcony is a wooden closed balcony projecting from a wall.

By contrast, a 'Juliet balcony' does not protrude out of the building. It is usually part of an upper floor, with a balustrade only at the front, like a small Loggia

Loggia

Loggia is the name given to an architectural feature, originally of Minoan design. They are often a gallery or corridor at ground level, sometimes higher, on the facade of a building and open to the air on one side, where it is supported by columns or pierced openings in the wall...

. Modern Juliet balconies often involve a metal barrier placed in front of a high window which can be opened.

Juliet balconies are named after Shakespeare's Juliet, who, in traditional stagings of the play Romeo and Juliet

Romeo and Juliet

Romeo and Juliet is a tragedy written early in the career of playwright William Shakespeare about two young star-crossed lovers whose deaths ultimately unite their feuding families. It was among Shakespeare's most popular archetypal stories of young, teenage lovers.Romeo and Juliet belongs to a...

, is courted by Romeo while she is on her balcony -- though in fact the play itself, as written, makes no mention of a balcony, but only of a window at which Juliet appears.