Everyone changes, especially in a different environment with different people. Bilbo Baggins is a good example. He changed from a timid, predictable hobbit to a clever, decisive, brave, loyal, responsible hobbit; he also gained a lot of confidence.
His first change was when "something Tookish woke up inside him, and he wished to go see The Great Mountains." It was then when he realized he wanted an adventure; he really did wanted to go see the mountains, but then 'he shuddered; and very quickly he was plain Mr. Baggins again'. He was interested, curious, and scared at the same time. When Bilbo heard that all of them may never return, he got so scared he screamed and fainted.
His second change was the encounter with the trolls. Even though it didn't seem that he changed a lot, he was braver, because he was the one who went first, he not only lead, he also managed to 'pick pockets'.
He was also responsible because he thought of the dwarves, and loyal, because he didn't give them away. This shows that Bilbo is trying to overcome his fears .
His third change was the riddles with Gollum. He became much more decisive: "'Go back?' he thought. 'No good at all! Go sideways? Impossible! Go forward? Only thing to do! On we go!'" From this I can tell that Bilbo became a much quicker thinker and faster at making decisions. He also became braver because even though he was afraid of Gollum, he still talked with him. He also won against Gollum, which is a big success for Bilbo, even though he did 'cheated' by not asking a riddle but a question, it still was a big success. He also very luckily, found the ring, which made him invisible to...