You have to realize that these two are different types of religions that people have all over the world. Islam is a type of religion wherein they believe that there is an almighty God that they call Allah. They believe that it is God who created everything, and they believe that they have to follow what Allah has said, especially through what their prophet Mohammed has stated.
Buddhism is another religion wherein they believe that there is a supreme being called the Buddha that watches over all people, but they do not believe that the Buddha is the creator. Rather, they believe that there are different creations that have already taken place.
Both of these religions shun certain practices. For example, those who believe in Islam do not eat pork because they believe that it is haram. Those who are Buddhists steer clear from drinking alcohol.