I got this answer from another website, its not my work but I thought it could help you guys out.
Answer:
Napoleon and Snowball are both young boars in Animal Farm. Napoleon is a fierce boar, with lots of strength, and one that everyone easily follows. Most of the other animals in the farm seem scared of Napoleon the young boar, and that's why they listen to whatever it is he has to tell them so closely. He is the type of boar that seeks opportunity, and always ends up getting his way regardless of the situation. Snowball however might be considered the thinker of the group, he teaches the animals of his ways and has a more intellectual or moral point of view that he is able to express with much ease. He is an idealistic boar and although he and Napoleon are vivacious, Snowball is way more vivacious than Napoleon. Although Snowball is a character with great animation, Napoleon is a character with much more depth in the story.