A debutante (or deb) (from the French débutante, "female beginner") is a young lady from an aristocratic or upper class family who has reached the age of maturity, and as a new adult, is introduced to society at a formal presentation known as her "debut" or "coming out". Originally, it meant the young woman was eligible for marriage, and part of the purpose was to display her to eligible bachelors and their families with a view to marriage within a select upper class circle. This traditional event varies by region, but is typically referred to as a debutante ball if it is for a group of debutantes. A lone debutante might have her own "coming-out party", or she might have a party with a sister or other close relative.

United Kingdom
In Australia, some debutante balls (or colloquially "deb balls") are held in year 11 or 12 of the Australian Government funded school system through the school, although some are held outside the school system by organisations such as the local chapter of Lions Club. Girls do not have to 'make their deb' and today many girls elect not to or see deb balls as irrelevant. Equally, the ongoing tradition indicates that the debutante ball as rite of passage is alive and well in Australia.
It is customary for the female to ask a male to the debutante ball, with males not being able to "do the deb" unless they are asked. Debutante ball students who are partaking in the official proceedings must learn how to ballroom dance. Debutante balls are almost always held in a reception centre or ballroom. Usually they are held late in the year and consist of dinner, dancing and speeches by the school captains. Schools often restrict invitations to the debutante ball to students within the grade level at one school, but single-sex schools tend to allow a partner with no association to the school to attend. The debutante ball traditionally is a rite of passage for some Australian school students, both male and female, and represents their coming of age. They are often, but not always, similar to American proms. [2].
The girl wears a white wedding dress-like ball gown, called a Debutante Dress, while the boy wears a tuxedo.
When a girl attends a non-Government school, the girl is invited to take part and her family pay for the ball. They are presented to the Governor of the State or other dignitary.

Australia
In Ireland, Debutante balls have most in common with the high school prom of the United States. This type of ball is referred to as a "debs" or a "debs ball". Each secondary school will host their own ball; usually in September/October. Most schools have the debs in the autumn after the final year, but some chose to begin the final year with the debs. In some schools, before the debs, a smaller ball, known as a pre-debs or mini-debs is held; usually January/February but sometimes as late as May. Often a Debs committee is established to organise a Debs. These are usually organised by someone other than the school itself. Debs balls occur at the end of the final year of second-level students, but there are many variations on when this can occur, some are as early as mid July, whilst others can be as late as Christmas. Traditionally a committee is created in the school to organise the event. Normally, the person asking someone else to the debs will pay for both tickets.
Many students worry about being invited or finding a date, though it is rare for students not to attend for this reason. Often, students try to find a date they have affections for. This is not always the case, and many attend with friends or in a group, not worrying about the dating aspect. Occasionally, depending on the school, students from the year below that studied the optional transition year, and so are a year behind, are entitled to go. Whether the female asks the male, or vice versa, is irrelevant. Boys are usually attired in dinner jackets with bowties, occasionally with brightly colored cummerbunds or waistcoats. Girls usually wear formal gowns or dresses adorned with a corsage given to them by their date. It is customary for boys to purchase an orchid or bouquet of flowers and/or a box of chocolates to give to their date's mother. Where the ball is held at a venue outside the locality, couples will sometimes travel to the venue by limousine, a tradition which has become more widespread as prosperity has increased.
Social class has no effect on the debs, each school has a debs, regardless of social status. People in informal dress can still be present, though this is a rare occurrence. Dancing is optional and never as formal as ballroom style, though it is polite for the male to ask his date to dance at least once, and to buy her all her drink during the night. Photographs from the event are often featured in local newspapers. It is common for attendees not to return home until the following morning, often going for breakfast together in groups in town (while still in their formal evening clothes) or to stay at someone else's house that night and return home, sometimes in a tired and emotional state!

Ireland
A cotillion or debutante ball in the United States is a formal presentation of young ladies, debutantes, to polite society. Debutantes are usually recommended by a distinguished committee or sponsored by an established member of elite society.
Wearing white gowns and satin or kid gloves, the debutantes stand in a receiving line, and then are introduced individually to the audience. The debutante is announced and then is walked around the stage, guided by her father who then presents her. Her younger male escort then joins her and escorts her away. Each debutante brings at least one escort, sometimes two. Many debutante balls select escorts and then pair them with the debs to promote good social pairings. Cotillions may be elaborate formal affairs and involve not only "debs" but junior debutantes, escorts and ushers, flower girls and pages as well. Every debutante must perform a curtsy also known as the Saint Johns Bow or a full court bow. This gesture is made as the young woman is formally presented.
Debutante balls exist in nearly every major city in the United States but are more common and a larger affair in the South. Many cities such as Dallas and Atlanta have multiple balls in a season. Dallas, for example, is home of the ultra-prestigious Idlewild debutante season. It also has less-pretentious debutante seasons such as The Dallas Symphony Orchestra Presentation Ball and La Fiesta de las Seis Banderas. They are often charity occasions, in which the parents of the young ladies, as well as all attending, must contribute a certain sum of money to the cause at hand. In New Orleans, Louisiana, a debutante is usually presented during the Carnival season.
As an alternative to a ball, and more commonly in the North, a young woman might have her own "coming-out party", given by her parents. Unlike a collective ball, which would be only held at a certain time of the year, such a party could be at any time of the year, but might well be scheduled around the debutante's birthday. In theory, the only women who could be invited would be those who had already made their debuts, thus affording a sort of rank-order to the debutante season.
Metropolitan (film), Whit Stillman's debut feature film, is a comedy of manners, set during the deb season in Manhattan.
In "She's the Man", a 2006 film, Amanda Bynes plays a tom boy soccer-loving girl, who initially dismisses the idea of being a debutante as "totally archaic", but in the end succumbs to it.
"The Debut", an episode of the The O.C. (a drama about upper class Californians), featured a representation of an American debutante ball.
"Presenting Lorelai Gilmore", an episode of Gilmore Girls shows Rory Gilmore as a debutante. She makes her debut at a DAR debutante ball that her grandmother helped put together.
"Waiting Tables", an episode of CSI: NY, featured the CSI team investigating the murder of a debutante. Medical examiner Evan Zao comments that he attended a debutante ball.
"Debut", an episode of Cold Case, tells the story of a young girl who is murdered the night of her debutante ball.
"Something New", a romantic comedy has a cottilion scene of upper class African Americans on the west coast.
"The Debut, a film about considered to be an accurate snapshot of contemporary Filipino American life, and touches upon a wide variety of cultural themes within the plot of a debutante event.

Latin America

Aristocracy
Boston Brahmin
Bachelor and Spinster Balls
Cotillion
Preppy
Social Register
White Anglo-Saxon Protestant