Religion is a touchy subject for many people.  It is largely a matter of personal faith, and literally hundreds of different belief structures (in fact there are hundreds of various Christian religions alone) constitute the religions of the world.  Touchy or not, religions have contributed immensely to World History in a variety of ways, blending with economics, politics, and even security concerns in all the countries across the globe.  The world has been changed by people trying to spread their faith, eliminate an "opposing" belief, or promoting their faith as a national priority.  That is the most important reason why religions needs to be understaood to comprehend the world.  They are also fascinating.

     While there are nearly countless religions, most historians recognize five major sets of beliefs that have impacted the planet to a large degree.  These five religion can then be divided into two categories.  The most influential in Europe are the Abrahamic Religions, which began in the Holy Land and spread to Western Civilization.  These include, in chronological order, Judaism, Christianity, and Islam.  The religions most influential in the Eastern World are Hinduism and Buddhism.