Twilight

Wikipedia:

Since the release of the first novel, Twilight, in 2005, the books have gained immense popularity and commercial success around the world. The series is most popular among young adults; the four books have won multiple awards, most notably the 2008 British Book Award for "Children's Book of the Year" for Breaking Dawn, while the series as a whole won the 2009 Kids' Choice Award for Favorite Book.

As of October 2010, the series has sold over 116 million copies worldwide with translations into at least 38 different languages around the globe. The four Twilightbooks have consecutively set records as the biggest selling novels of 2008 on the USA Today Best-Selling Books list and have spent over 235 weeks on the New York TimesBest Seller list for Children's Series Books.

Thus far, the first three books have been made into a series of motion pictures by Summit Entertainment; the film adaptation of Twilight was released in 2008 and the second, The Twilight Saga: New Moon, was released on November 20, 2009. The third film, The Twilight Saga: Eclipse, was released June 30, 2010.

Why was Harry Potter Popular?

http://tanorthburg.hubpages.com/hub/What-Makes-Harry-Potter-Popular

Oprah

http://www.youtube.com/watch?v=PQ8C1XM9JIc

"one day every child in the world will know his name"

The film poster follows the codes and conventions of a film poster through the information at the bottom and the symbol of the production company in this case Warner Bros. It also uses the image of the Hogwarts Express which was also used on the book front cover allowing both poster and front cover to relate, however also showing there will be some differences in the movie through changing the colour of the train to black and red. We are also able to see the setting and the characters who resemble what they should actually look like in the novel, which is something the films did really well on. The poster uses a blueish tint which adds to this magical and mysterious affect however it also allows everything to look real.

The front cover sticks to the codes and conventions of a books front cover through the writing of the title on the front page and the authors name, while also adding a little quote from a review "this is a terrific book" the image denotes the Potter boy standing in front of the red "Hogwarts Express" looking surprised with clouds of smoke and magic stars with platform "9 3/4" showing an image that we attain from reading the book foreshadowing what is to come. The cloud of smoke and stars connote the magic within the book, this along side the image of the Hogwarts Express and Harry looking surprised with the many colors allows it to look like he is being submerged into the magical world which is literally what happened in the book.Already allowing us to know that it is part of the fantasy genre.There is also a stark contrast between the Hogwart express and the other train connoting the "wizarding world" to be exciting and unreal while the "muggle world" looks mundane and natural. The overdose of red used on the front cover connotes danger which Harry is put in a lot in the novel and allows the novel to be presented as a fast paced series of drama too.

Harry Potter

Wikipedia:
Since the 30 June 1997 release of the first novel Harry Potter and the Philosopher's Stone, the books have gained immense popularity, critical acclaim and commercial success worldwide. As of June 2011, the book series has sold about 450 million copies and has been translated into 67 languages and the last four books consecutively set records as the fastest selling books in history.
A series of many genres including fantasy and coming of age (with elements of mystery thriller. adventure and romance), it has many cultural meanings and references. There are also many other themes including love and prejudice.
 The books have been made into an eight-part film series by Warner Bros. Pictures, with the seventh book split in two parts; it is the highest grossing film series of all time

Due to the novels success and it being well known, could this be the reason why it was converted into a film?

Seeing as the context of the novel was very interesting and it had so many genres that it could relate to attracting a mass audience it was a good book to turn into a film. Also being produced by the Warner Bros allowed the film to gain much popularity and attention in the beginning as Warner Bros are one of the major production companies in the industry.