[DanaC]

From that wiki page:

Adopted by dwarfs after the deaths of his human parents, Carrot grew up in the mines. He is "six feet tall and nearly as broad across the shoulders". His dwarfish name is Kzad-bhat, which, roughly translated, means "Head Banger", a logical nickname for a 6-foot-6-inch-tall (1.98 m) man living in a mine built by 4-foot-tall (1.2 m) dwarfs. He was quite surprised the day he found out that he was human. His adoptive father thought that he ought to go and live amongst humans, and found him a job with the Ankh-Morpork Night Watch under the misapprehension that they were respected and respectable.

Carrot joined the Night Watch while it was only a small group of misfits who ran from evildoers rather than arrest them (see Guards! Guards!). He had difficulty with this attitude, as his "old-fashioned" view of justice led him to arrest the leader of the entirely legal Thieves' Guild on his first day. He since has learned to understand the city a bit better. The city learned about him as quickly when he won in a fight against every miscreant in the Mended Drum tavern, including the then splatter (like a Bouncer but harder) Detritus the troll.

Captain Carrot has made quite a name for himself, rapidly and effortlessly coming to know everyone in the city by name and tax papers. He is big on paperwork and organization and always (often to the dismay of his girlfriend, Angua) takes time to see all sides of a story before getting involved. When Sam Vimes planned to retire after his marriage to Lady Sybil Ramkin, Carrot was named his successor. He is not particularly skilled in comma placement and has a bit of trouble with the whole concept of "i before e." He is considered "the Disc's most linear thinker:" For instance, as part of a murder investigation, he interviews Death.

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Carrot is often thought of as non-threatening, which is a dangerous conclusion if you are the unlucky person who disappoints his honest nature. People think of Carrot as being simple, however their mistake is in confusing "simple" with "stupid". Carrot's simplicity is his cunning. In Soul Music, Carrot adds supplementary questions to the quiz machine in the Mended Drum, asking players who was responsible for recent crimes and frequently making arrests as a result. Carrot often sees the bright side of life. When Angua, a werewolf, tells him that her brother Andrei is stuck in wolf form and is forced to live as a champion sheepdog, Carrot notes that at least he's a champion. Carrot has also promised Angua that, should she ever follow in her brother Wolfgang's murderous footsteps, he will be the one to stop her.

Carrot is a stereotypical "perfect" policeman. Totally honest, law abiding and determined to be friends with everyone. People of all species can't help wanting to behave well in his presence. He has an attitude of loving everyone. His philosophy of love for everyone has caused distress for Angua. She worries that his love toward her is equal to that he gives everyone else and not special. While he would place the welfare of the public above hers (and his own), when she was in danger he travelled to the rim of the Disc to save her.