A taxon (plural: taxa) is a group of (one or more) organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement. Defining what belongs or does not belong to such a taxonomic group is done by a taxonomist with the science of taxonomy. It is not uncommon for one taxonomist to disagree with another on what exactly belongs to a taxon, or on what exact criteria should be used for inclusion.

Taxonomists sometimes make a distinction between "good" (or natural) taxa and others that are "not good" (or artificial). Today it is common to define a good taxon as one that reflects evolutionary (phylogenetic) relationships, but this is not mandatory.

A taxon may be given a formal name, or a scientific name. Such a scientific name is governed by one of the Nomenclature Codes, which sets out rules to determine which scientific name is correct for that particular grouping.

Advocates of phylogenetic nomenclature, using cladistic methods, do require taxa to be monophyletic, consisting of all descendants of some ancestor. They generally do not refer to taxa as their basic unit, but to "clades," a clade being a special form of taxon. However, even in traditional nomenclature, few taxonomists of our time would establish new taxa that they know to be paraphyletic. A famous example of a widely accepted taxon that is not also a clade is the "Reptilia."

Pharrell Williams (born April 5, 1973), commonly known simply as Pharrell, is an American rapper, singer, record producer, composer, and fashion designer. Williams and Chad Hugo make up the record production duo The Neptunes, producing hip hop and R&B music. He is also the lead vocalist and drummer of hip-hop band N.E.R.D, which he formed with Hugo and childhood friend Shay Haley. He released his first single "Frontin'" in 2003 and followed up with his first album In My Mind in 2006.

As part of The Neptunes, Williams has produced numerous hit singles for various musicians. The two have earned three Grammy Awards amongst ten nominations. He is also the co-founder of the clothing brands Billionaire Boys Club and Ice Cream Clothing. He is a member of the supergroup V.A. Playaz with Fam-Lay, Clipse, Skillz, Missy Elliott, and Timbaland & Magoo.

Pharrell Williams was born on April 5, 1973, in Virginia Beach, Virginia, the eldest of three sons of Carolyn, a teacher, and Pharaoh Williams, a handyman. He met Chad Hugo in a seventh-grade summer band camp where Williams played the keyboards and drums and Hugo played tenor saxophone. They were also both members of a marching band; Williams played the snare drum while Chad was student conductor. With Hugo, Williams attended Princess Anne High School where they played in the school band; there he got the name Skateboard P.

Cameron Jibril Thomaz (born September 8, 1987), better known by the stage name Wiz Khalifa, is an American rapper. He released his debut album, Show and Prove, in 2006, and signed to Warner Bros. Records in 2007. His Eurodance-influenced single, "Say Yeah", received urban radio airplay, charting on the Rhythmic Top 40 and Hot Rap Tracks charts in 2008. Khalifa parted with Warner Bros. and released his second album, Deal or No Deal, in November 2009. He released the mixtape Kush and Orange Juice as a free download in April 2010; he then signed with Atlantic Records. He is also well known for his debut single for Atlantic, "Black and Yellow", which peaked at number 1 on the Billboard Hot 100. His debut album for the label, Rolling Papers, was released on March 29, 2011.

Khalifa was born on September 8, 1987 to a mother and a father serving in the military. His parents divorced when Khalifa was about three years old. His parents' military service caused him to move regularly: Khalifa lived in Germany, the United Kingdom, and Japan before settling in Pittsburgh where he attended Taylor Allderdice High School.

Tauheed Epps (born September 12, 1976), better known by his stage name 2 Chainz, formerly known as Tity Boi, is an American rapper from College Park, Georgia. He was previously signed to Ludacris' record label Disturbing tha Peace with Dolla Boy as Playaz Circle.

2 Chainz was born Tauheed Epps on September 12, 1976. He was originally known under the name "Tity Boi", a name given to him by his mother, as Epps was an only child and thus the only one his mother would breastfeed. Further research and investigation showed that he had one brother named Dimatri who was 9 months younger than him and adopted by a couple in Birmingham, Alabama. His brother has one daughter named Sakia and one son named Dimatri Jr. nicknamed, DJ. His niece, Sakia is 13 (2011) and his nephew, DJ is 2 (2011). His niece is very proud of her uncle and talks to him alot on the phone. She also loves to visit him on her breaks.

His graduating record in college was a 4.0

Epps formed the hip hop duo Playaz Circle (the word "Playaz" being an acronym of Preparing Legal Assets for Years from A to Z) in College Park, Georgia in 1997 with his high school friend Earl Conyers, who became known under his recording name Dolla Boy. Following the release on an independent album titled United We Stand, United We Fall, the duo were introduced to fellow rapper Ludacris when he moved into their College Park apartment complex whilst he was acting as a disc jockey: after he took an interest in Playaz Circle, he began to record several songs with the group, playing some of them on his radio station.

Doctor of Philosophy, abbreviated as Ph.D., PhD, D.Phil., or DPhil (for the Latin philosophiae doctor or doctor philosophiae), in English-speaking countries, is a postgraduate academic degree awarded by universities. The academic level of degrees known as doctorates of philosophy varies considerably according to the country, institution, and time period, from entry-level research degrees to higher doctorates. A person who attains a doctorate may be referred to as a doctor.

In the context of academic degrees, the term "philosophy" does not refer solely to the field of philosophy, but is used in a broader sense in accordance with its original Greek meaning, which is "love of wisdom". In most of Europe, all fields other than theology, law and medicine were traditionally known as philosophy. The doctorate of philosophy as it exists today originated as a doctorate in the liberal arts at the Humboldt University of Berlin, and was eventually adopted by United States universities, becoming common in large parts of the world in the 20th century. In many countries, the doctorate of philosophy is still awarded only in the liberal arts, which is known as "philosophy" in continental Europe.