"Weasley is the surname of a pure-blood family (though the most recent generation has many non-pureblood members). Their names are Ginny, Ron, Fred, George, Percy, Charlie, Bill, Molly, and Arthur Weasley. The Weasleys know many other wizarding families, including the Blacks, Prewetts, Longbottoms, Crouches, Delacours, and Potters, as well as the Muggle Granger family. All members of the Weasley family are red-haired and Sorted into Gryffindor house upon attendance of Hogwarts School of Witchcraft and Wizardry.

The family home, known as the Burrow, is located just outside Ottery St. Catchpole, in Devon, England. The Weasleys live near other magical families such as the Diggory, Fawcett, and Lovegood families.

When Harry Potter befriended Arthur and Molly Weasley's youngest son, Ronald Weasley, the Weasleys became a second family to Harry. The Burrow became Harry's home away from home (he only resided with the Dursley family out of necessity), and Arthur and Molly served as de facto godparents in Sirius Black's absence.

They were included in the Sacred Twenty-Eight list, published in the Pure-Blood Directory by the 1930s. However, they deplored their inclusion in the list, because they said the had ancestral ties to many interesting Muggles. Their protests earned these families the opprobrium of advocates of the pure-blood doctrine, and the epithet 'blood traitor'. [...]

The Weasleys, unlike many other pure-blood families, willingly associate with Muggles, Muggle-borns, and half-bloods and do not consider themselves superior to others because of their blood status."
Source: Harry Potter Wiki