Gods and Deity in Japan

Amaterasu (天照) : *Shinto Goddess*  Amaterasu is the Godess of the sun and even of the universe. She's one of the major deity of Japan. She might appear under different variation of her name :  Amaterasu-ōmikami (天照大神／天照大御神／天照皇大神), or Ōhirume-no-muchi-no-kami (大日孁貴神). Amaterasu means "shining in heaven". The emperors of Japan are supposed to be direct descendant of that Goddess. 

Hachiman [八幡]: *Shinto God* Hachiman is the patron god of the Minamoto family and of wariors, therefor of the samurai in general but he isn't a God of War he is a protective God of Japan and Japanese people and is even worshipped by peasants and fishermen.
The modern reading is "hachiman" but an ancient reading that is still found for the same kanji is [Yawata] or [Yahata]. The Kanji means "God of the Eight Banners", the eight banners being a sign from heaven of the divine birth or Emperor Ojin. The animal related to this god is the dove.
He's the second most revered god in Japan's shinto shrines (first being Inari)

Susano (素戔嗚命/須佐之男命) or Susano-o Mikoto. He is the God of storms - and fertility even if it's not his main attribut - and lives in the sea. He is the brother of Amaterasu and Tsukuyomi.
After he went to the land of the dead, their father Izanagi washed his face in Tachibana river in Miyazaki) Amaterasu was created when he washed his left eye, Tsukuyomi his right eye and Susano when he washed his nose. (With that you can tell right away who will be the messy kid)
After messing with his father and his sister (and I mean badly messing : like putting a dead horse in his sister house) he got everyone angry and there is punished (they cut his bear and his nails ... I guess a manicure salon is a torture place for japanese gods) and he is banned from the sky. 
Once on earth he has the good idea to defeat a dragon with 8 heads in Koshii prefecture. In the tail of the dragon he find a sword Kusanagi no Tsurugi . He gives it as a present to his sister who finally forgive him. Then Susano got married, got many kids and started the Izumo dinasty.

Tenjin Sama (天神様) : We will here use the name under which he usually goes as a deity. But Sugawara no Michizane (菅原道真) (845-26 mars 903) is also know under the names of Kan Jōshō (菅丞相), Tenmangū (天満宮) or Kanke (菅家). He is the Grand-son of de Sugawara no Kiyotomo He is a man of letter, a poet and a politician of Japan's Heian Era. He is famous for his poetry skills especially chinese poetry. Even though, as a Minister of Emperor Daigo,  he was forced into exile in kyushu under the pressure of the powerful Fujiwara family. He was rehabilitated after his death and is venerated by japanese as a god of culture named Tenjin. Japanese students are used to invoke this deified character to bring them luck in exams.

A 1857 print by Utagawa Toyokuni III showing the sun goddess Amaterasu, 

the most important deity of the Japanese Shinto religion.