Floo Network

The Floo Network is a mode of transportation in the wizarding world in which a witch or wizard goes from one place to another by means of Floo powder and a fireplace. Many fireplaces are connected in the Floo Network, and the traveller need only speak the desired fireplace they wish to arrive at very clearly as they stand in the emerald green flames.

Regulation and usage
The network is governed by the Floo Network Authority, a section of the Department of Magical Transportation of the Ministry of Magic. This department is located on Level Six of the Ministry. The Floo Network Authority controls which fireplaces are connected to the Floo Network, which requires specialized magic. Travelling by way of the Floo Network can be done without specialised magic, and can be preferable for wizards too young to Apparate or those without access to other forms of transportation, such as broomsticks.

When travelling by Floo, a witch or wizard must clearly pronounce the location they want to go, or they may be misdirected to the wrong place.

Body transport
This network connects all wizarding fireplaces that utilise Floo powder as a mode of transportation. Muggle homes are not connected to the Floo Network unless special, temporary arrangements are made, which do not require that the Authority visit the location. The connection can be made from the Ministry of Magic.

To access the network, one must toss a handful of Floo Powder into a fireplace, walk into the heatless, emerald green fire, and declare the desired destination. It is apparently also important for the traveller to keep their elbows close to their body. During the trip, the traveller will notice other fireplaces and hearths zooming past, but it is not possible for the traveller to see these locations clearly as the speed of travel is too great.

Head-only transport
One may also use the Floo Network to speak to someone in another location by merely putting their head through the green fire, as Sirius Black did to talk to Harry in latter's fourth and fifth years at Hogwarts. The Floo Network can also be used to transport inanimate objects. For example: In 1994, Molly Weasley used the fire tongs to put a piece of toast into Amos Diggory's mouth while he was talking to Arthur Weasley via the Floo Network after the Quidditch World Cup incident.

As Sirius Black could use the fire to talk to Harry in fourth and fifth year, but in Harry's sixth year, a special arrangement had to be made from the Ministry to enable students to arrive at Hogwarts, it seems that head-only transport is possible even if human transportation is not. Otherwise, intruders, including Sirius Black, could simply use the fire in the common room to circumvent the castle's defences.

Known uses

 * Tumblr_mtncpg9Xnb1rhjaiio2_250.gif[[Harry Potter]] first travelled via the Floo Network in 1992 when he journeyed from The Burrow to London. However, instead of saying "Diagon Alley", Harry was nervous and said "diagonally". Therefore he accidentally ended up at Borgin and Burkes in Knockturn Alley.
 * In 1994, the Floo Network was temporarily connected to the Dursley's, as a favour to Arthur Weasley, so that he could transport Harry back to The Burrow in preparation of the upcoming trip to the 1994 Quidditch World Cup that Harry would be attending with the Weasley family and Hermione. The Dursley's, however, had an electric fire and Arthur Weasley had to blast open the fireplace to get out because he was stuck in there with Ron, Fred and George.
 * In 1996, Harry used the Floo Network connection in Dolores Umbridge's office to contact Sirius Black at 12 Grimmauld Place, as her fireplace was one of the only ones not being monitored. Harry attempted to contact Sirius a second time on 17 June, but was caught by Umbridge while speaking to Kreacher.
 * At the end of the Christmas holidays in Harry's sixth year at Hogwarts, numerous students including Harry, Hermione and the Weasleys, used the Floo Network to travel back to Hogwarts.
 * In 1997, when the Ministry was overthrown by Lord Voldemort, only the homes and offices of senior Ministry officials were connected to the Network.

Known Floo Network connections

 * Diagon Alley
 * The Leaky Cauldron
 * Gambol and Japes Wizarding Joke Shop
 * Magical Menagerie
 * Knockturn Alley
 * Borgin and Burkes
 * Hogwarts School of Witchcraft and Wizardry
 * Gryffindor Common Room
 * Defence Against the Dark Arts Professor's office
 * Transfiguration Professor's office
 * Head of Slytherin's office
 * Dolores Umbridge's office (temporarily)
 * Hogwarts kitchen
 * The Burrow
 * Ministry of Magic
 * Atrium
 * Little Whinging
 * 4 Privet Drive (temporarily)
 * London
 * 10 Downing Street
 * 12 Grimmauld Place

Appearances

 * Harry Potter and the Chamber of Secrets
 * Harry Potter and the Chamber of Secrets (film)
 * Harry Potter and the Goblet of Fire
 * Harry Potter and the Goblet of Fire (film)
 * Harry Potter and the Order of the Phoenix
 * Harry Potter and the Order of the Phoenix (film)
 * Harry Potter and the Order of the Phoenix (video game)
 * Harry Potter and the Half-Blood Prince
 * Harry Potter and the Deathly Hallows
 * Harry Potter and the Deathly Hallows: Part 1
 * Harry Potter and the Deathly Hallows: Part 1 (video game)
 * LEGO Harry Potter: Building the Magical World
 * LEGO Harry Potter: Characters of the Magical World
 * Harry Potter and the Forbidden Journey
 * Harry Potter LEGO Sets

Notes and references
Flohnetzwerk Red Flu Réseau des cheminées Metropolvere Каминная сеть Sieć Fiuu