Marl or marlstone is a calcium carbonate or lime-rich mud or mudstone which contains variable amounts of clays and silt. The dominant carbonate mineral in most marls is calcite, but other carbonate minerals such as aragonite, dolomite, and siderite may be present. Marl was originally an old term loosely applied to a variety of materials, most of which occur as loose, earthy deposits consisting chiefly of an intimate mixture of clay and calcium carbonate, formed under freshwater conditions; specifically an earthy substance containing 35-65% clay and 65-35% carbonate. It also describes a habit of coralline red alga. The term is today often used to describe indurated marine deposits and lacustrine (lake) sediments which more accurately should be named marlstone. Marlstone is an indurated rock of about the same composition as marl, more correctly called an earthy or impure argillaceous limestone. It has a blocky subconchoidal fracture, and is less fissile than shale. The term marl is widely used in English-language geology, while the terms Mergel and Seekreide (German for "lake chalk") are used in European references.

Marlon Williams (born September 30, 1962), better known as Marley Marl, is an American DJ and record producer, who is considered one of the most important and influential hip-hop producers in the history of hip hop.

In Hip-Hop's Golden Age, Marley Marl was the house producer of the Juice Crew, known for The Bridge Wars, a feud with Boogie Down Productions seen as one of the earliest and most influential hip hop beefs. The Juice Crew included Big Daddy Kane, Biz Markie, Roxanne Shanté, Kool G Rap & DJ Polo, Craig G, MC Shan and Masta Ace, and produced many songs for outside artists including King Tee, LL Cool J, and Lords of the Underground. He was also an important figure in the careers of Eric B. & Rakim, producing their first hits "My Melody" and "Eric B Is President".

Marl was the first to sample a breakbeat and reprogram it, which he did with The Honey Drippers' "Impeach the President" breakbeat on the MC Shan single "The Bridge" from 1985. This was an extremely important feat as it completely changed the way hip hop beats were made, as well as other sample based genres. In his early records, Marl mixed James Brown samples and synthetic beats in a fashion previously unheard of, for the most part.

MC Shan (born as Shawn Moltke September 6, 1965) is an American rapper from Queens, NYC. He is perhaps best known for collaborating with Snow in "Informer", an international number one hit single.

Born and raised in the Queensbridge Projects located in Long Island City a section in Queens, New York City, Shan is the cousin of old school hip hop producer Marley Marl. In 1985, Shan started in MCA Records with his first & only major single Feed The World. Despite the success, he was dismissed from MCA because "the rhymes you wrote was wack", according to KRS-One from his song South Bronx. Not long after, Shan moved to Cold Chillin' Records due to his relationship with Marl, and joined Marl's Juice Crew All-Stars. After a few singles were released, MC Shan's debut album Down By Law came out in 1987.

Shan also found himself to be a key player in the noted hip hop rivalry the Bridge Wars between the Juice Crew and Boogie Down Productions. The feud was started when Shan and Marl released a song called "The Bridge" as a B-side to "Beat Biter," itself an answer record directed at L.L. Cool J. KRS-One responded with "South Bronx," and the Juice Crew replied with "Kill That Noise." Slate magazine described it as follows: "In 1986, it was a beef that launched the star of KRS-One, when his withering attacks on MC Shan effectively ended his rival's career." Boogie Down Productions then released "The Bridge is Over," widely celebrated among hip hop fans as the paramount diss track.^{[citation needed]} Years later, MC Shan remade "The Bridge" into "Da Bridge 2001," and strongly denied the bridge "was over", saying:

James Todd Smith (born January 14, 1968), better known as LL Cool J (an abbreviation for Ladies Love Cool James), is an American rapper, entrepreneur, and actor from Bay Shore, New York. He is known for romantic ballads such as "I Need Love", "Around the Way Girl" and "Hey Lover" as well as pioneering hip-hop such as "I Can't Live Without My Radio", "I'm Bad", "The Boomin' System", and "Mama Said Knock You Out". He has released thirteen studio albums and two greatest hits compilations, including 2008's Exit 13, the last for his record deal with Def Jam Recordings. He has also appeared in numerous films, and currently stars as NCIS Special Agent Sam Hanna on the CBS crime drama television series NCIS: Los Angeles.

As he grew older, Smith found a way to escape the effects of his abuse, and his bullying attitude: hip-hop music. He fell in love with it at the age of nine, and by 11 he was writing lyrics and making his own songs with some DJ equipment his grandmother gave him to stop him riding motorcycles or doing karate. Before too long, LL was an established member of the Hip-Hop community in his area. He gained notoriety through his many rap battles against well-established MCs, including the battle against Chicken and Porn that rocketed him to fame.

Marcel Theo Hall (born April 8, 1964,Harlem, New York) better known by his stage name, Biz Markie, is an American rapper, beatboxer, DJ, comedian, singer, reality television personality, and commercial spokesperson. He is best known for his single "Just a Friend", an American Top 10 hit in 1989. In 2008, "Just a Friend" made #100 on VH1's list of the 100 greatest hip hop songs of all time.

Markie has been called "the Clown Prince of Hip Hop."

Biz Markie's career began on Long Island, New York in the early 1980s, where he established his reputation for beat-boxing and rapping. MC Shan and Roxanne Shante were part of Marley Marl's Cold Chillin' Records, and Biz beatboxed on Shante's underground hit "Def Fresh Crew" (1986). This lent credibility to his recording career and put Cold Chillin' on the map. In the same year, Biz Markie's debut single, "Make the Music With Your Mouth, Biz", was released on Prism Records. He released his debut album, Goin' Off, which attracted a fair amount of attention, largely due to the lead single, "Make the Music With Your Mouth, Biz". The album also featured the underground hit singles "Nobody Beats The Biz", "The Vapors" and "Pickin' Boogers".