Mirror of Erised

"Men have wasted away before it, not knowing if what they have seen is real, or even possible."

- Albus Dumbledore explaining the danger of the mirror to Harry Potter

The Mirror of Erised is a magic mirror, which, according to Albus Dumbledore, shows the "deepest and most desperate desire of our hearts." The happiest person in the whole world would look in the mirror and see a reflection of exactly the way he or she is. Inscribed across the top of the frame is the following text:
 * Erised stra ehru oyt ube cafru oyt on wohsi

Reversing the inscription and rearranging the spaces produces:
 * I show not your face but your heart's desire

History
Upon seeing the mirror for the first time in 1991, Harry Potter saw himself surrounded by his dead parents and relatives. Ron Weasley, overshadowed by his brothers and striving to be noticed by others, saw himself as the Quidditch captain and Head Boy, and holding up the Quidditch cup. Albus Dumbledore, who was with Harry at the time, claimed to see himself holding a pair of thick, woolen socks, telling Harry that "one can never have enough socks." If this had been true, it would suggest that Dumbledore was so content with life that the only things he wished for were small things. However, Dumbledore was joking, the matter being a very personal one.

As revealed to Harry in 1998 Dumbledore would have seen his dead relatives (his sister, Ariana Dumbledore; his mother, Kendra Dumbledore; and his father, Percival Dumbledore); as well as his brother Aberforth reconciled to him when he looked in the Mirror of Erised. Dumbledore felt extremely guilty about the deaths of his parents and sister and his estrangement from his brother.

In 1992, the Mirror was the final guardian of the Philosopher's Stone. Dumbledore placed an enchantment on the mirror, hiding the stone inside it and allowing the mirror to transfer it to anyone who wanted to find the stone but not use it. Anybody else would see himself making gold or the Elixir of Life (as Professor Quirrell found out for himself). Initially, the mirror was kept in an unused classroom and tucked out of sight (by Dumbledore) and was discovered by Harry Potter. Over the next few days, Harry proceeded to visit it as often as he could to see his parents' faces. Eventually, Dumbledore stepped in and moved the mirror, concerned about Harry becoming too attached to it. Later, Harry encountered it again, this time focusing on finding the stone, and, uninterested in using the stone for his own purposes, saw his reflection pocketing the stone, at which it magically appeared in his real pocket. It is unknown exactly what happened to the mirror after this.

Albus Dumbledore

 * A pair of thick, woollen socks (claimed)
 * His family alive and well

Harry Potter

 * His parents and extended family
 * Himself, holding the Philosopher's Stone
 * As of 1997, Lord Voldemort defeated and dead

Ron Weasley

 * Himself as Quidditch Captain and Head Boy, better than his brothers.

Hermione Granger

 * Herself and her friends alive and unscathed, Voldemort defeated, and herself in a romantic embrace with a "certain person".

Quirinus Quirrell

 * Himself presenting the Philosopher's Stone to his master, Lord Voldemort

Lord Voldemort

 * Himself, all powerful and immortal

Etymology
The word "Erised" (pronounced eer-ih-sehd) is "desire" spelled backwards meaning the name could also be known as the "mirror of desire." The backwards text is a symbol of the odd nature of the mirror, because the mirror works in a very backwards way from regular mirrors in a way that it shows the inside and not the outside of a person. The inscription around the mirror reads "Erised stra ehru oyt ube cafru oyt on wohsi" The message backwards is "I show not your face but your heart's desire."

Appearances

 * Harry Potter and the Philosopher's Stone
 * Harry Potter and the Philosopher's Stone (film)
 * Harry Potter and the Philosopher's Stone (video game)
 * Harry Potter and the Order of the Phoenix (film) 
 * Harry Potter and the Half-Blood Prince
 * Harry Potter and the Deathly Hallows

Notes and references
Miroir du Riséd