J. K. Rowling says Luna is sort of the "anti-Hermione," as Luna believes things on faith alone and Hermione grounds her beliefs on facts and logic. Hermione tries repeatadly to convince Luna that her beliefs are nonsense, to no avail. Luna sees Hermione as being narrow-minded and Hermione sees Luna as being very gullible. Hermione seems to have realized that Luna won't falter in her beliefs by the end of Harry Potter and the Order of the Phoenix, as when Luna says she and her father are going on expedition to Sweden to catch a Crumple-Horned Snorkack, Hermione responded in a polite manner rather than try to convince her that there is no such thing as a Crumple-Horned Snorkack.
Luna is in Ravenclaw and Ginny Weasley's year, her fourth in Harry Potter and the Order of the Phoenix. She is called "Loony Lovegood" behind her back, although she is aware of this and doesn't mind. Some of her classmates regularly steal her possessionss and hide them for the fun of it. When she told Harry this in an offhanded conversation, she unintentionally won his sympathy. Harry offered to help her find her lost things, but she refused. It is interesting that Luna dosen't care about her own image, but does care what people think of her father's magazine.
Luna was never mentioned before Harry Potter and the Order of the Phoenix, though in Harry Potter and the Goblet of Fire it was mentioned that the Lovegood family lived in the area of The Burrow. It is never stated that this is Luna's family.
Luna has waist-length dirty blond hair and is described as having a dazed look. Luna joined Dumbledore's Army and was involved in the battle in the Department of Mysteries (Along with Harry Potter, Ron Weasley, Hermione Granger, Neville Longbottom and Ginny Weasley.)
The name "Luna" is Latin for the moon. This obviously refers to Luna's absentmindedness and clearly unconventional patterns of thought, as in ancient times the moon was thought to induce insanity in people (Hence the word "Lunatic," which, intrestingly enough, is the source of Luna's nickname, "Loony"). The origin of Luna's surname are more ambigious. Obviously, it combines the English words "love" and "good", both of which have very positive conotations. This could refer to her kind character, or could be simply an idiosyncrasy of the author. Her last name could also be referece to Elliot Lovegood Grant Watson, who wrote numerous books highlighting the insufficiencies of Darwinism after he was raised by a mother who adored Darwin. Perhaps a reference to how Luna's father's magazine attacks assumed beliefs?
Luna says her late mother was a "quite extraordinary witch" who liked "to experiment." She died when one of her spells went "rather badly wrong." Luna says it was "rather horrible" and admits she still feels sad about it sometimes, but is relieved she still has her father. As Luna witnessed her mother's death at the age of nine, she has been able to see Thestrals since she arrived at Hogwarts. In the Department of Mysteries, Luna claimed to able to hear voices behind a mysterious veil in the Death Chamber (often refered to in the world of fanfiction as the "Veil of Death" or the "Black Veil", though it is never named in the actual book,) which Harry could also hear. Luna says those behind the veil, including her mother, are not gone but actually just "lurking out of sight." When she explained this to Harry, he didn't know what to make of it- another unusual belief of Luna's, or perhaps a comforting metaphor? This question will probably be answered in the forthcoming Harry Potter books, as we see to what extent the deceased Sirius Black still plays a role in Harry's life.