Baldness implies partial or complete lack of hair. Balding is part of the wider topic of "hair thinning". The degree and pattern of baldness can vary greatly, but its most common cause is male and female pattern baldness, also known as androgenic alopecia, alopecia androgenetica or alopecia seborrheica – an alternative term used primarily in Europe.

Pattern balding should not be confused with alopecia areata, which commonly involves patchy hair loss. Extreme forms of alopecia areata are alopecia totalis, which involves the loss of all head hair, and the most extreme form, alopecia universalis, which involves the loss of all hair from the head and the body.

More than 95% of hair thinning in men is male pattern baldness, or androgenetic alopecia. Male pattern baldness is characterized by hair receding from the lateral sides of the forehead (known as a "receding hairline") and/or a thinning crown (balding to the area known as the ‘vertex’). Both become more pronounced until they eventually meet, leaving a horseshoe-shaped ring of hair around the back of the head.

Ariana Grande-Butera (born June 26, 1993) is an American actress, singer, and dancer. She made her performance debut on Broadway at age 15. Recently, she has gained attention for her role as Cat Valentine on the Nickelodeon sitcom Victorious.

Grande was born and raised in Boca Raton, Florida. She is of Italian descent, half Sicilian, half Abruzzese.

In 2008, Grande played the role of Charlotte in the musical 13 on Broadway, for which she won a National Youth Theatre Association Award. When she joined the musical, Grande left her high school, North Broward Preparatory School, but continued to be enrolled. The school sent materials to her for study with tutors. She played the role of Miriam in the first reading of the forthcoming musical Cuba Libre composed by Desmond Child. Grande teaches music and dance to children in South Africa each year as a member of Broadway in South Africa.

Grande plays the character Cat Valentine on the Nickelodeon television show Victorious, which premiered in March 2010.

Katheryn Elizabeth Hudson (born October 25, 1984), known by her stage name Katy Perry, is an American singer, songwriter and actress. Perry grew up with gospel music, and during her first year of high school she pursued a music career as Katy Hudson, releasing her first studio album called Katy Hudson which failed to chart. She recorded a solo album later, which was never released. After signing with Capitol Music Group in 2007, her fourth record label in seven years, she adopted the stage name Katy Perry.

She first gained recognition with the release of her first mainstream album, One of the Boys in 2008, which spawned three Billboard Hot 100 top-ten songs—"I Kissed A Girl", "Hot n Cold" and "Waking Up In Vegas". Perry supported the album with her Hello Katy Tour. In 2010, her third studio album, Teenage Dream (2010), which topped the Billboard 200 chart, and spawned five number one singles—"California Gurls", "Teenage Dream", "Firework", "E.T." and "Last Friday Night (T.G.I.F.)"—Teenage Dream was the only album (after Michael Jackson's Bad)—to do so, and the first female in history to achieve this milestone. She embarked on the California Dreams Tour, which grossed nearly $60 million worldwide. Perry re-released the album under the name of Teenage Dream: The Complete Confection on March 26, 2012, and the re-release has already spawned the number-one single "Part of Me".