Who is Pippin in the movie?
Peregrin Took is a very distant relative of Frodo Baggins, and the best friend of Merry Brandybuck. He is a very young, inquisitive but rather naive and clumsy Hobbit, who joins the Fellowship almost by accident.

Who was Pippin in the book?
Peregrin Took is a distant relative of Frodo Baggins, and one of his dearest friends. He is quite young for a Hobbit, but still insists on travelling with Frodo, first to Crickhollow, later to Rivendell and in the end even to Mount Doom – though he never gets there…

Changes in Fellowship of the Ring
Introductions
We first hear about Pippin at the beginning of the second chapter, ‘The Shadow of the Past’, when Tolkien describes the years between Bilbo’s departure and Gandalf’s reappearance with news about the Ring: ‘…his closest friends were Peregrin Took (usually called Pippin), and Merry Brandybuck…’
The first time Pippin really appears on the scene of the actions is when Frodo, Sam and Pippin leave for Crickhollow (1.III.).
In the movie, Merry and Pippin are introduced together at Bilbo’s birthday party, pulling a prank with some of Gandalf’s fireworks.

General Character Changes
Pippin is the youngest of the hobbits, and in every respect a Took: though he is a bit naive (because of his youth), he’s also very enthusiastic, a loyal friend and very brave.
In the movie, we see Pippin mostly being clumsy or stupid and so set off a chain of events that bring about a dramatic change: he mentions Frodo’s real name in the Prancing Pony, he wants to come along on the quest but has no idea what he’s getting himself into (2.II) and he drops an entire skeleton in the well in Moria…

Though still in line with the original portrayal, Pippin’s character is largely reduced to his naive side in the movie, thus lending him for ‘comic relief’: Pippin’s naivety often brings a lighter note to a scene or sequence, and also enables the script writers to further the plot. This dimension of Pippin’s character is not wholly absent in the books, but it was greatly enlarged.

Incidents and Accidents
As I already mentioned above, most of Pippin’s actions really are clumsy accidents or funny comments: the prank with the fireworks, the comment about the mushrooms and the request to join Frodo on his journey to Mordor are funny diversions; his slip of the tongue in Bree or the skeleton-accident in Moria have far greater consequences. Add to that the Scottish accent and Billy Boyd’s hilarious facial expressions, and you get the image of a comical character.

In truth, most of these Pippin-related accidents don’t occur in the book, or were greatly re-worked for the movie:
– the prank with the fireworks: Gandalf is the one lighting the Smaug-fireworks, Merry and Pippin aren’t even mentioned. (1.I.)
– stealing Farmer Maggot’s cabbages: Pippin’s a friend of the farmer through Merry. The only one who stole from the good hobbit was Frodo, who used to steal mushrooms when he was little. (1.IV)
– mentioning Frodo’s name in Bree: Pippin was telling the mayor of Michel Delving about Bilbo’s party, and Frodo tried to stop him before he got to the disappearance by singing a silly song in the middle of the Inn. (1.IX.)
– ‘ash in my tomatoes’: Strider is the one who urges the hobbits to make a fire, because ‘fire is our ally in the wilderness’.
– ‘Where are we going?’: Pippin and Merry insist on joining the fellowship, to stay with Frodo as they promised in Crickhollow. It is Gandalf, in the end, who decides to allow Pippin to come. (2.II.)
– throwing rocks in the lake outside Moria: It’s not Merry and Pippin who ‘wake’ the Watcher in the Water: it already stirred when the fellowship tried to cross the lake and Frodo stepped into the water. Later, it is Boromir who starts throwing pebbles in the water out of frustration. (2.IV.)
– the well-incident: Pippin throws one small pebble into the well, and nothing comes of it for a whole day. (2.IV.)

Pippin’s one heroic deed, the decoy-trick when the Uruk-hai are threatening to capture Frodo that Merry devises, is not mentioned in the book.

Indescernable Background Hobbits
A lot of viewers have a problem keeping Merry and Pippin apart. In the book, their characters were more different, and they weren’t always teamed up. This is one of the side effects of the enlargement of Sam‘s part in the movies, and the reduction of mainly Pippin but also Merry to comic relief.

Some simple tricks to keep them apart:
– Merry’s the smart one. This is actually true to the book: Merry is a serious young hobbit, who makes an almost aristocratic impression. He’s more thoughtful and moderate than Pippin, but he’s also a little older so that may have something to do with it.
– Pippin’s the one with the Scottish accent. That helps a lot in keeping the two hobbits apart, but on the downside it gives Pippin an extra touch of funniness. Merry’s the one with the quite indiscernible accent, at least for a not-native speaker. So if anyone knows what accent he has, the Viewpoint submission form is the place to be!
– Merry’s the one with the yellow vest and the bigger nose.