Comparing and contrast animal farm in the movie and in the book

Today we watched the animal farm movie and it was somehow similar to the actually book. It was about 80percent same. For example, the movie showed that they are having a meeting and a cat come in late; and this is actually in the book. However something is different, the movie is less detail than the story and some of the word spoken by the characters in the movie aren't the same as the book. In the book Mr.Jones didn't fire a gun but in the movie he did. And in the book the song is sing more detail but in the movie the song wasn't sing that detail comparing to the story of animal farm. Characters are more introduced in the book but character aren't introduced a lot in the movie.