Dune: Arrakis, (derived from the Arabic name ar-rāqiṣ, "the dancer", originally a star-name for Mu Draconis) later Rakis (known colloquially as "Dune") is a fictional desert planet featured in the Dune novels by Frank Herbert, where it is the home of the Fremen (Zensunni wanderers) and later, the Imperial Capital under Muad'Dib's Empire. Arrakis is the third planet orbiting the star Canopus, and it in turn is orbited by two moons, one of which has the image of the desert kangaroo-rat, Muad'Dib, on it; the other possessing the image of a human hand.

Dune is a dry, desert planet with no natural bodies of water or precipitation. Giant sandworms (Shai-Hulud, later called Shaitan) and their immature forms of sandtrout and sandplankton were among the few fauna on the planet when it was discovered. As indicated by large salt flats, Arrakis once had oceans; the depletion of the oceans, the primary result of which was desertification, was probably caused by the impact or near miss of a comet or other quasi-planetary body. This event caused the loss of much of the Arakeen atmosphere, allowing most of the oxygen and water to escape into space. This is thought to have occurred approximately 50 million years before the Imperium's creation. This catastrophic loss of oxygen led to the extinction of nearly all native flora and fauna. One of the few forms to survive were tiny worms of the phylum protochordata. One of these forms was shaihuludata, an anaerobic burrowing worm that was the basal species from which Shai-Hulud, the sandworm of Arrakis, evolved. Rather than sandworm creating desert, it was desert that created sandworm. The mass extinction of all of shaihuludata's predators and competitors for food allowed the animal, in a manner somewhat analogous to the evolution of unique faunal forms on isolated Terran islands, to take the evolutionary path that would not only re-oxygenate the Arakeen atmosphere, but also create the spice melange with all of its immense consequences for humanity. Early in the history of Arrakis, the Imperium made several attempts to terraform the planet, which resulted in an abundance of Terran desert life on the planet, but met with little success, as the local sandtrout "encyst" any open water on the planet.
source: The Dune Encyclopedia

First and foremost, "Dune" (as it first become known on 20th century Earth) is a series of science fiction novels written by Frank Herbert, first published in 1965. A winner of the Hugo Award and Nebula Award for outstanding science fiction, Dune is popularly considered one of the greatest science fiction novels of all time, and is frequently cited as the best-selling science fiction novel in history. Dune spawned five sequels: Dune Messiah, Children of Dune, God Emperor of Dune, Heretics of Dune, and Chapterhouse Dune.  Dune is set far in the future amidst a sprawling feudal galactic empire where planetary fiefdoms are controlled by noble Houses that owe allegiance to the Imperial House Corrino. The first novel tells the story of young Paul Atreides, heir apparent to Duke Leto Atreides and scion of House Atreides, as he and his family relocate to the planet Arrakis, the universe's only source of the spice melange; a substance that is a geriatric drug that gives the user a longer lifespan, greater vitality, and heightened awareness, unlocking prescience in some subjects (depending upon the dosage and the consumer's physiology). In a story that explores the complex interactions of politics, religion, ecology, technology, and human emotion, the fate of Paul, his family, his new planet and its native inhabitants, as well as the Padishah Emperor, the powerful Spacing Guild, and the secretive female order of the Bene Gesserit, are all drawn together into a confrontation that will change the course of humanity.

In 1975 Alejandro Jodorowsky tried to film the Dune story as a ten hour long feature with collaboration from Orson Welles, Salvador Dalí, Gloria Swanson, H. R. Giger and others. The music would have been done by Pink Floyd, but the project was never finished. Some preparations were later used in the Alien films.

In 1984, a screen adaptation was successfully made by director David Lynch. Lynch's vision of Dune was surreal, moody, and dark. The film starred Kyle MacLachlan as Paul Atreides. Although it became a cult favorite, the film cost $42 million to produce and had a domestic gross of only $27.4 million. It was also criticized by Herbert fans who objected to the director's liberal departure from the novel's storyline.

In 2000, produced by New Amsterdam Entertainment in association with Blixa Film Productktion and Hallmark Entertainment Distribution, the Sci Fi Channel broadcast a three-part mini-series based on the Dune novel by Frank Herbert. Although in many respects faithful to the book, the miniseries did boast some stylistic changes. For example, whereas Herbert's ornithopters were described as truly birdlike in their flight, the miniseries' ornithopters more closely resembled insects. Contention surrounding the correct pronunciation of Herbert's "Fedaykin" aside, the miniseries opted for a Western pronunciation more distant from the Arabic-sounding one used in Lynch's film that would seem appropriate given the extensive, Arabic-themed terminology in the novel (the correct pronunciation is what it looks like, "Fed-ay-kin", but at this sounds similar to "Fedayeen", the characters pronounce it "Fed-die-kin"). Some fans were upset by the Fremen's eyes, believing that the nearly phosphorescent, light blue coloring was not faithful to Herbert's description, "blue within blue" (in the miniseries, you can still see the iris and whites of the eyes, but in the book heavy spice addiction makes the eye look like a solid blue ball).

some source material provided by: Wikipedia's Dune Page

• Dune: The Butlerian Jihad
• Dune: The Machine Crusade
• Dune: The Battle of Corrin

• Dune: House Atreides
• Dune: House Harkonnen
• Dune: House Corrino

   Dune 7 Novels

• Hunters of Dune 
• Sandworms of Dune
  

On his "Dune 7 Blog", Kevin J. Anderson has stated that the book jacket summary will be the following:

Frank Herbert's epic continues...

Since 1986, millions of readers have longed to know the ending of the uncompleted story which began in Heretics of Dune and continued in Chapterhouse: Dune. Before his death, Frank Herbert wrote a detailed outline for his chronological grand finale, under the working title of Dune 7, and placed it along with additional material about Dune in a bank safe deposit box. There it remained hidden for ten years, and the great Dune chronicles remained unfinished. His son Brian Herbert and Kevin J. Anderson have now completed this epic in two volumes, finally answering the questions Dune fans have been debating for almost two decades. Hunters of Dune is the first of two breathtaking journeys into the world of Dune as it remakes itself in a new form after its greatest crisis. Fleeing from the monstrous Honored Matres -- dark counterparts of the Bene Gesserit Sisterhood -- Duncan Idaho, a woman named Sheeana who can talk to sandworms, the military genius Bashar Miles Teg, and a group of desperate refugees explore the boundaries of the universe. Aboard their sophisticated no-ship, they have used long-stored cells to resurrect heroes and villains from the past including Paul Muad'dib and his love Chani, Lady Jessica, Thufir Hawat, even the traitor Doctor Yueh, all in preparation for a final confrontation with a mysterious outside Enemy so great it can destroy even the terrible Honored Matres. And, deep in the hold of their giant ship, the refugees carry the last surviving sandworms from devastated Arrakis, as they search the universe for a new Dune. The authors are currently writing Sandworms of Dune, which will complete the story. This grand conclusion brings together the great storylines and characters from the time of the Butlerian Jihad to the original Dune series and beyond.

 

This has raised some controversy as well, with many fans doubting the authenticity of these "notes" containing such a storyline, especially regarding the "resurrected heroes" (bear in mind that at the end of "Chapterhouse: Dune" it was revealed that the Tleilaxu Scytale had hidden cell samples of major characters from the entire series, and thus this was already somewhat implied).