The following is a list of magical objects used in the fictional universe of Harry Potter in the original book series, as well as in the adapted film series.
In Harry Potter and the Order of the Phoenix, Hermione Granger creates fake, enchanted Galleons (wizard money) that are used for communication between members of Dumbledore's Army (DA). Like real Galleons,[1] the coins have numerals around the edge. On normal Galleons these serial numbers signify the goblin who cast the coin; on the enchanted Galleons, the numbers represent the time and date of the next DA meeting. Due to the coins being infused with a Protean Charm, once Harry Potter alters his, every coin changes to suit. The coins grow hot when the numbers change to alert the members to look at their coins.
In Harry Potter and the Half-Blood Prince, Draco Malfoy uses a pair of enchanted coins to bypass the communication limits imposed on Hogwarts, thus managing to keep in contact with Madam Rosmerta, whom he had placed under the Imperius Curse. Draco reveals he got the idea from Hermione's DA coins, which were themselves inspired by Lord Voldemort's use of the Dark Mark to communicate with his Death Eaters.
In Harry Potter and the Deathly Hallows, Neville Longbottom uses the DA's coins to alert people such as Luna Lovegood and Ginny Weasley that Harry, Ron and Hermione have returned to Hogwarts.
A Howler is a scarlet-red letter sent to signify extreme anger or to convey a message very loudly and publicly. When it is opened, the sender's voice, which has been magically magnified to a deafening volume, bellows a message at the recipient and then self-destructs itself by burning.[2] If it is not opened or there is a delay in opening it, the letter smoulders, explodes violently, and shouts the message out even louder than normal.[HP2] In the film version, the Howler folds itself into an origami-style set of lips and teeth and shouts the message out, and then shreds itself into scraps of paper before it burns itself.
In Harry Potter and the Chamber of Secrets, Ron Weasley receives a Howler from his mother, Molly Weasley, after he steals his father's enchanted car and flies it to Hogwarts with Harry. Neville Longbottom confesses that he had once gotten a Howler from his grandmother Augusta, stating that he ignored it and that the result was horrible. Subsequently, Neville receives another Howler from his grandmother after Sirius Black uses his list of passwords to enter the Gryffindor common room in Harry Potter and the Prisoner of Azkaban. Hermione receives one in Harry Potter and the Goblet of Fire after Rita Skeeter publishes an false article about a relationship between Hermione and Harry. In Harry Potter and the Order of the Phoenix, Dumbledore sends Harry's aunt Petunia Dursley a Howler to remind her of the agreement to allow Harry to live at Privet Drive when Harry's Uncle Vernon attempts to throw him out.