A Tarot deck consists of 78 cards, each with its own meaning. There are several methods of drawing and interpreting the cards. I do not work with traditional Tarot decks, and instead work with modified versions that do not contain "dark" energy cards. These decks still contain the 5 major suits: the Major Arcana and the four Minor Arcana and follow the same rules and principles of traditional decks.
Oracle cards all differ in their content, each with cards related to the purpose of the deck. Most commonly these decks contain 44 cards and have no set layout for interpretation. Often the reader will shuffle the cards until one sticks out of the deck and pull it out. The reader will continue to shuffle until no more cards stick out.