Before attempting to discuss the advent of Buddhism in Japan, it would be proper to discuss Shintoism first. Shintoism is the first religion the Japanese people have ever known, tracing back to the origins of the Japan itself as a country. In other words, it can be termed as the indigenous faith of the Japanese people.
Since ancient times the Japanese have worshiped all the items that comprise the nature around them, such as the mountains, islands, rocks, trees, wind, water, fire etc., They have also paid their heartfelt respect and gratitude to their great ancestors, kings, scholars and mythological figures from traditional texts.
Tree designated as "Kami" at Yuki Shrine
There is no single god in Shintoism but it comprised of multitude of gods. These gods are called "Kami". In a way Shintoism had evolved as a way of worshipping the nature and thanking the nature for providing them with sustenance and protection. For example the worship of the wind god "Kami Kaze", originated when Japan was in the midst of being invaded by the Yuan Navy from China. But this navy was destroyed by great winds that were at that time created in the oceans (Typhoons). So a legend has began that the goddess of wind (Kami Kaze) actually saved Japanese from a certain defeat and destruction. Legends like this are abundant in Japan and every Kami that helped Japanese during their lives has evolved into a worshiped deity.
Shintoism has no official scriptures or prophets. There are no sects or denominations. The worshipped gods (Kamis) are enshrined in Shrines. These Shrines can belong to a village, street, ward or a city. They can be small or (very) large. Some of them built by one single common person or some of them built by the Emperors of the day. Some shrines exist in alters inside a single household. That is why there are thousands (yes, thousands...) of shrines in Japan.
Usually these Shrines are called "Jinja" or "Taisha" or "Jingu". The
words Jinja and Taisha represent small/medium and big shrines
respectively. The word Jingu is designated to Shrines that were built for honoring the royalty by the royalty. The "Toshogu" shrines are also famous that are built in the later part of Japanese history commemorating the Tokugawa royalty. Japanese also perform weddings at these Shinto Shrines.
Almost all the Shrines follow similar type of setting. Usually there is a wooden or a stone Torii (gate) present before the visitors enter into the main premises of the Shrine. These Toriis are usually painted in Vermillion color to ward off the evil spirits. The Shrines grounds are paved with gravel and contain lanterns made with either stone, copper or iron. These Lanterns are symbols of light and offering to the God.
Koma Inu (Lion Like Statues)
You will also see lion like figures made of stone (called Koma Inu) in these premises. One of these figures have mouth open (male lion) one with mouth closed. Some have horns and are very elaborate. They represent good luck.
Most Shrines also have figures of foxes (Kitsune) or figures of cows at various locations within the Shrine's premises.
Before entering the main worship hall, visitors rinse their hands and mouth with pure water at a Wash Basin (Chozuya) to purify their bodies.
The procedure for rinsing is as follows: First, take a ladle in your right hand, and scoop water and pour over your left hand. Shift the landle to your left hand and rinse with your right. Shift the ladle again to your right and scoop water to pour it over one's palm. Take a small sip of water to rinse your mouth (please do not drink this water). Wash your left hand once again. Return the ladle face down to the wash basin.
Procedure for cleansing (Atsuta Jinja, Nagoya City)
There are other artifacts you will see in a typical Shrine; rice-straw rope (Shimenawa) with paper strips which demarks the border between the inner worship hall with the outside hall, horse paintings or figures. There are also Omikuji's that you can buy, which are used to tell somebody's fortune.
Before you walk into the main shrine (main worship hall), there are one or two stages outside, usually just in front of the main shrine. These stages are used to perform dances during the festivals, associated with the Shrine.
There is a specific procedure worshiping at a shrine. These steps are:
1) Proceed towards the alter.
2) Offer some coins or bills in the offering box.
3) Bow twice deeply.
4) Clap your hands twice
5) Bow once deeply, express gratitude and pray for fulfillment of your wishes.
The foreign visitors to Shrines look at worshipers clapping at these Shrines with some level of awkward fascination but please note that it is the way to worship at a Shrine.