1. In Egyptian Mythology, Toth, or Thoth, was the god of wisdom, of knowledge, of healing and of teaching. (Very similar to Mercury to the Romans, and Hermes to the Greek.) Toth was also the god of the Moon. He has been depicted with the head of an Ibis, and with the head of a Babboon. Sometimes he even has the body of a baboon.
According to most myths, Toth was the brother of Ra. In Memphis, he was considered to be the supreme deity and successor of Ptah, instead of Ra.
The god of wisdom (Thoth is the Greek corruption of the original Egyptian Tahuti), Thoth was said to be self-created at the beginning of time, along with his consort Ma'at (truth). The two produced eight children, of which the most important was Amen, the hidden one, who was worshiped in Thebes as the Lord of the Universe.
Thoth was depicted as a man with the head of an ibis bird, and carried a pen and scrolls upon which he recorded all things. He was shown as attendant in almost all major scenes involving the gods, but especially at the judgement of the deceased.
It was widely believed that Thoth invented the magical and hermetic arts, and thus the Tarot deck, especially its revision by Aleister Crowley, is often referred to as the "Book of Thoth".
[Source: Shawn C. Knight, "Egyptian Mythology FAQ" ]
2. The Toth Tarot is the name Aleister Crowley gave to his version of the Tarot.