To many people, the Japanese religion of Shinto is more or less a complete mystery. They may know what the Shinto shrines look like, or might have some knowledge of the fact that Shinto practitioners worship something called "kami"... for most people, though, the knowledge of this old religion ends there.
Like many religions, Shinto is actually made up of groups with differing beliefs and forms of worship. Unlike most religions, though, the number of groups is very small... there are actually only four major types of Shinto worship. The four types are actually very much alike (which is another difference from many major religions), and practitioners of each respect the beliefs of those who practice other forms of Shinto. Additionally, all who practice Shinto are taught to be mindful and respectful of the religious beliefs of others, and there are many in Japan who practice both Shinto and Buddhism without difficulty.
The type of Shinto worship that's usually listed first when talking about the different types of Shinto is the Koshitsu Shinto, or the Shinto of the Imperial House. Koshitsu Shinto is the rites and rituals performed by the emperor (referred to in the Japanese constitution as "the symbol of the state and of the unity of the people") as well as male and female clergy members. The ritual of Niinamesai is the most important of all of the rituals performed by the emperor, as it gives an offering of the first harvest of the year to the deities to thank them for the year's prosperity.
The next type of Shinto worship is the Jinja Shinto, or the Shrine Shinto. Jinja Shinto is the original form of the religion, and was once closely aligned with Koshitsu Shinto since the emperor was worshiped as a living god until the end of World War II. This form of Shinto is focused on the building of shrines (called "Jinja") to the various gods and spirits (called "kami") of the earth, land, and world. Each shrine has an individual history, and is built to honor and worship a specific kami... therefore the traditions of each area where a shrine is located is a bit different from any other shrine. This is a part of the reason that there is no central doctrine or scripture to Shinto in any form.
The third Shinto group is the Shuha Shinto, which is also known as the Sect or Sectarian Shinto. Shuha Shinto is made up of 13 different sects, each of which follows its own doctrine and many of which focus almost entirely on one or two specific kami. Though it does share some of the basic Shinto beliefs, Shuha Shinto is the most removed from the other forms, and in some sects almost borders on monotheism.
Finally, there is the Minzoku Shinto, or the Folk Shinto. This is not truly a separate form of Shinto... instead, it is merely the beliefs and practices of the commoners, who simply followed their beliefs and never took the time to organize them into a separate system of worship. Folk Shinto cannot truly be separated from Jinja Shinto, though it was segregated by a past emperor so that the government could establish official times and dates for festivals and rituals.
