Hollywood has a tendency to alter or ignore certain details and scenes that take place in a book when its movie is created. The Hunger Games movie happens to be very similar to the book, although some specific aspects were noticeably different. In the book, the author spends a great amount of time discussing the events leading up to the games (introductions, training, interviews, etc.), while the movie gives a brief overview of these details and spends most of the time showing the games. However, the story line and plot manage to consistently resemble the book. Also, the book is in first person from Katniss' point of view, while the movie is in third person. This gives the viewer a chance to see behind the scenes and what happens with he gamemakers while Katniss is not around.
There are a few major differences between the book and the movie. For starters, Haymitch is not present at the reaping in the movie, whereas in the book he is portrayed as a drunken mess and he falls off the stage. This is the first time the reader's are introduced to Haymitch, and it is an important detail in the book in order to set a tone for the audience about his character. Once the reaping is over and the tributes are preparing to leave for the Capitol, Madge, the mayor's daughter, pays Katniss a visit. She asks Katniss to wear a mockingjay pin to represent District 12 and shows her support for Katniss. The movie shows Katniss buying a mockingjay pin from an older woman at the hob and Madge is not even mentioned or shown in the movie at all. Once Peeta and Katniss arrive at the capital, not much time is spent showing everything that they had to go through before the games began. At the introductions, Cinna and Haymitch commanded Peeta and Katniss to hold hands on the chariot, but in the movie it was all Peeta's idea, with no guidance from the others. In the book, the two were also told to do everything together at training, and act like friends. Haymitch and Peeta came up with the plan together to announce his crush on Katniss at the interviews. The movie is opposite of the book in which the girls go first in the training sessions and interviews, as opposed to the boys going first in the book. When it was finally time to enter the arena, Cinna was the only person who was present to send off Katniss into the arena, but in the book Haymitch and Effie were all present until she went through the tubes.
In the arena there are also several differences between the movie and the book. For example, the parachutes are sent with notes from Haymitch in the movie, whereas in the book there are no notes and Katniss must figure out the message Haymitch is trying to send. After Katniss dropped the tracker jacker nest on the careers, she passes out in the forest and Rue uses the leaves to cure her stings while she is asleep; however, in the book Katniss finds Rue on her own and Rue shows her how to use the leaves to cure her stings afterwards. In the book when Rue dies, District 11 sends Katniss the bread, but in the movie this does not occur. This scene was important to show that District 11 appreciated Katniss' effort to keep Rue safe and that they fully support her. Once the gamemakers announce the decision that there can be two victors, Katniss immediately runs to find Peeta. The movie shows that he has camouflaged himself into the ground and he sticks his hand out to grab Katniss' leg, but in the book Katniss had to sought him out and find him for herself. In order to bring the games to an end in the book, the gamemakers drain the stream so that Peeta and Katniss must go towards the cornucopia, where Cato resides, but in the movie this does not take place. Peeta and Katniss simply move towards the cornucopia on their own, when they are attacked by the muttations. Cato is waiting on the cornucopia for them while they are trying to escape these muttations. In the book, however, the author depicts Cato as first being chased by the muttations, which is how Peeta and Katniss figure out that they need to run.
Despite these differences, I do think that the movie was very similar to the book in most ways. Although the book was better than the movie, the plot of each were basically the same and the movie did not change the authors idea of the Hunger Games.