The abbreviation "L.D.S." stands for "Latter Day Saints." The offical name of the Mormons is "The Church of Latter Day Saints." I believe that they prefer this name to that of "Mormons." In regard to doctrine, you will do well to go to a Mormon website [this is a site for (ex) - Jehovah's Witnesses]. On the Internet, you will find information that is both "pro" Mormon (that is to say, favorable toward Mormons) and "anti"-Mormon. I guess that you should consult both varieties in order to get both sides of the story.
In regard to doctrine, I do not know much about them. Like the Jehovah's Witnesses, Seventh Day Adventists and Christian Scientists, the Mormons had their origins in 19th-century America. All of these groups were formed in the 1800's in the U.S. In addition to the Bible, the Mormons have their own scriptural book called the Book of Mormon. Mormons are usually quite traditional in their viewpoints and conservative in their politics. They have a number of doctrines which deviate very far from "standard" Christianity. Many people do not regard them as Christians, although they themselves say they are Christians. Again, if you are interested in their doctrines, just go to Google and type in "Mormons" or "Church of Latter Day Saints."