Your father left this in my possession before he died. It is time it was returned to you. Use it well.
-- Anonymous note accompanying the Cloak (PS12)
The Invisibility Cloak is a specific magical cloak belonging to Harry Potter which provides him or the wearer (or wearers) with complete invisibility.
For Christmas in 1991, Harry received the Invisibility Cloak anonymously (although later revealed to have been sent by Albus Dumbledore) (PS12). He makes use of the Cloak many times over the next few years.
The weave is so fine that an Invisibility Cloak is “strange to the touch, like water woven into material” (PS12). It is one of the legendary Deathly Hallows (DH21). Dumbledore explains that the true magic of the Cloak is its ability to conceal more than one person. He explains this to Harry:
“And the Cloak . . . the true magic of which, of course, is that it can be used to protect and shield others as well as its owner …” (DH35).
“I mean to say, it is not a travelling cloak imbued with a Disillusionment Charm, or carrying a Bedazzling Hex, or else woven from Demiguise hair, which will hide one initially but fade with the years until it turns opaque. We are talking about a cloak that really and truly renders the wearer completely invisible, and endures eternally, giving constant and impenetrable concealment, no matter what spells are cast at it.” (DH21).
Some believe it to be the cloak of Death itself, as stated in “The Tale of the Three Brothers“. Dumbledore believes otherwise:
“Whether they met Death on a lonely road … I think it more likely that the Peverell brothers were simply gifted, dangerous wizards who succeeded in creating those powerful objects. The story of them being Death’s own Hallows seems to me the sort of legend that might have sprung up around such creations.” (DH35).
Notes and interesting facts
On her original JKR website in the FAQ section, Jo specified that the NAQ ("Never Asked Question") was:
"Why did Dumbledore have James' invisibility cloak at the time of James' death, given that Dumbledore could make himself invisible without a cloak?"
She goes on to say that:
"However, nobody has ever asked me about it, and they really should have done.... There IS a significant - even crucial - answer."
Dumbledore explains in the final book that he wanted it as one of the Deathly Hallows, which he was trying to possess:
"....our interest in the Cloak was mainly that it completed the trio, for the legend said that the man who united all three objects would then be truly master of death, which we took to mean, invincible...." (DH35)
From the Web
Writing by J K Rowling on WizardingWorld (Pottermore):
Dumbledore and the Invisibility Cloak by raisin_gal
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