In the popular Harry Potter series of fantasy novels by JK Rowling, an Auror is a specially trained employee of the Ministry of Magic who tracks Dark Wizards and brings them to justice. Aurors are extremely talented and committed individuals, representing some of the most highly educated and trained wizards in the employ of the Ministry of Magic. The job of an Auror is perceived as highly glamorous by many, and it can also be extremely dangerous. Presumably the position pays reasonably well, in recognition of the long training time and considerable on the job danger.
Aurors are necessary within the wizarding community because of the existence of Dark Wizards, wizards who practice the Dark Arts. Many of these wizards are followers of Lord Voldemort. Aurors track and apprehend Dark Wizards with the goal of reducing crime in the wizarding and muggle worlds alike, and also in the hope of getting information about Voldemort's activities. They appear to have extensive personal powers, including the ability to use Unforgivable Curses against Dark Wizards, should the need arise.
In order to become an Auror, a wizard must perform extremely well in school, taking a minimum of five Nastily Exhausting Wizarding Tests (NEWTs), all with grades above “Exceeds Expectation.” The Ministry requires Aurors to sit for NEWT exams in Potions, Charms, Transfiguration, and Defense Against the Dark Arts, with Auror candidates pursuing optional electives of choice such as Divination or Arithmancy. Applicants are also put through a background check, and a series of aptitude tests designed to measure performance potential.
If an Auror is accepted as an employee by the Ministry, he or she undergoes an additional three years of training in advanced defensive and fighting techniques, along with tracking, concealment, stealth, and disguise. Just as is the case in school, Aurors are tested and graded on their performance in these subjects. Once trained, an Auror becomes a member of an elite law enforcement crew headquartered on the second floor of the Ministry of Magic's underground complex. In Harry Potter and the Order of the Phoenix, Harry visits Auror headquarters and gets to see the cubicles in which Aurors work, along with meeting several Aurors.
Readers are introduced to Aurors in Harry Potter and the Goblet of Fire, when they meet retired Auror Alastor Moody. In Harry Potter and the Order of the Phoenix, readers meet active Aurors such as Nymphadora Tonks and Kingsley Shacklebolt. Many Aurors are also clandestine members of the Order of the Phoenix.