In geometry, an angle is the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle. Angles are usually presumed to be in a Euclidean plane, but are also defined in non-Euclidean geometry.

Angle is also used to designate the measure of an angle or of a rotation. This measure is the ratio of the length of a circular arc by its radius. In the case of an angle (figure), the arc is centered at the vertex and delimited by the sides. In the case of a rotation, the arc is centered at the center of the rotation and delimited by any point and its image by the rotation.

The word angle comes from the Latin word angulus, meaning "a corner". The word angulus is a diminutive, of which the primitive form, angus, does not occur in Latin. Cognate words are the Greek ἀγκύλος (ankylοs), meaning "crooked, curved," and the English word "ankle". Both are connected with the Proto-Indo-European root *ank-, meaning "to bend" or "bow".

Euclid defines a plane angle as the inclination to each other, in a plane, of two lines which meet each other, and do not lie straight with respect to each other. According to Proclus an angle must be either a quality or a quantity, or a relationship. The first concept was used by Eudemus, who regarded an angle as a deviation from a straight line; the second by Carpus of Antioch, who regarded it as the interval or space between the intersecting lines; Euclid adopted the third concept, although his definitions of right, acute, and obtuse angles are certainly quantitative.

Sarah Ann McLachlan, OC, OBC (born January 28, 1968) is a Canadian musician, singer and songwriter. Known for her emotional ballads and mezzo-soprano vocal range, as of 2009, she has sold over 40 million albums worldwide. McLachlan's best-selling album to date is Surfacing, for which she won two Grammy Awards (out of four nominations) and four Juno Awards. In addition to her personal artistic efforts, she founded the Lilith Fair tour, which showcased female musicians. The Lilith Fair concert tours took place from 1997 to 1999, and resumed in the summer of 2010. Since 2006 she has also been known as a highly visible supporter of the ASPCA, as well as various other charities.

Sarah McLachlan was born on January 28, 1968, and adopted in Halifax, Nova Scotia, Canada. As a child, she took voice lessons, along with studies in classical piano and guitar. When she was 17 years old and still a student at Queen Elizabeth High School, she fronted a short-lived rock band called The October Game. One of the band's songs, "Grind", credited as a group composition, can be found on the independent Flamingo Records release Out of the Fog and the CD Out of the Fog Too. It has yet to be released elsewhere. Her high school yearbook predicted that she was "destined to become a famous rock star."

Kurt Steven Angle (born December 9, 1968 in Mt. Lebanon, Pennsylvania) is an American professional wrestler, amateur wrestler and actor. He is currently under contract with Total Nonstop Action Wrestling, where he is a former five-time TNA World Heavyweight Champion. He is also known for his time in the World Wrestling Federation / Entertainment (WWF/E), and for being the only Olympic gold medalist in the history of professional wrestling.

Angle was involved in amateur wrestling during both high school and college. In college at Clarion University of Pennsylvania, he won numerous accolades, including being a two-time National Collegiate Athletic Association Division I champion. After graduating, he won a gold medal in freestyle wrestling at the 1995 World Wrestling Championships. Angle then competed in the 1996 Summer Olympics in Atlanta, Georgia, where he won a gold medal in heavyweight freestyle wrestling. Kurt Angle is also one of only four people to complete a Grand Slam in amateur wrestling which is the junior nationals, the NCAAs, the World Championships and the Olympics. He was named the greatest shoot wrestler and one of the top 15 college wrestlers of all time by USA Wrestling.

Paul Michael Levesque (born July 27, 1969) is an American professional wrestler, wrestling executive, and actor better known by his ring name Triple H, an abbreviation of the ring name, Hunter Hearst Helmsley. Currently, Levesque works in the front office of WWE as the Executive Vice President of Talent and Live Events, and as Triple H appears on television as the (storyline) Chief Operating Officer, and part-time wrestler.

Levesque began his wrestling career in the International Wrestling Federation as Terra Ryzing before joining World Championship Wrestling (WCW) in 1994. After briefly using the Ryzing name, he changed his character to Jean-Paul Lévesque, a French-Canadian aristocrat which would be similar to his character Hunter Hearst Helmsley, that he used in his early years with the World Wrestling Federation (WWF) from 1995 onward. He later abbreviated his name to Triple H and adopted an alternative image in the D-Generation X (DX) stable. After the dissolution of DX, Triple H was pushed as a main event wrestler, winning several singles championships. As part of a storyline Triple H married Stephanie McMahon, who later became his real-life spouse. In 2003, Triple H formed another stable known as Evolution, and reformed DX with Shawn Michaels in 2006 and 2009. He is heavily involved in the writing process of WWE programming, and holds complete creative control over his television character's storylines, win/loss record, and championship reigns.

Brock Edward Lesnar (/ˈlɛznər/; born July 12, 1977) is an American professional wrestler, actor, former mixed martial artist and amateur wrestler, signed with WWE and appearing on its Raw brand. He is also a former UFC Heavyweight Champion and former #1 ranked mixed martial arts (MMA) Heavyweight by Sherdog; he was ranked #5 before he announced his retirement at the end of 2011. Lesnar is an accomplished amateur wrestler, winning the 2000 NCAA heavyweight wrestling championship and placing second in 1999, losing in the finals to 1999 world freestyle wrestling champion and future New England Patriots offensive lineman Stephen Neal.

He gained prominence in World Wrestling Entertainment (WWE) from 2002 to 2004, where he is a former three-time WWE Champion, becoming the youngest WWE Champion at age 25 with his first reign. Lesnar was the 2002 King of the Ring and the winner of the 2003 Royal Rumble. After leaving WWE, Lesnar pursued a career in the NFL. He played during the preseason for the Minnesota Vikings, but ended up being a late cut. Lesnar returned to professional wrestling at the end of 2005, and joined New Japan Pro Wrestling (NJPW), where he won the IWGP Heavyweight Championship in his first match. He was officially stripped of the title by NJPW in July 2006, and took the physical belt with him to Inoki Genome Federation (IGF), where he was still recognized as IWGP Champion until June 2007.