Islamic Art and Rules

It was very interesting to learn and know the rules of what kinds of pictures and drawings are not or accepted in Muslim homes and places of worship. I know that calligraphy is a very important kind of art in decorating Mosque . The reading mentioned that Muslims have to be careful about their way of displaying pictures because most prayers are done at Muslim homes. I did not know that display of images and pictures of prophets are forbidden in Islam. I thought Mosques were decorated with pictures of people, animals and other things when I looked them (Mosques) from outside. In Islam, “Statues are believed to bring danger of idolatry” (JCM, 407). It seemed to me that Islam is the only Religion, which rejects statues and display of human and animal pictures in Muslim homes. But I was wondering about Muslim leaders who have their statues displayed everywhere in their countries. How does Islam consider those statues? What kinds of materials besides Arabic letters are used to embellish Muslim Mosques?