I've started writing a series of articles for LoveToKnow outlining the symbolism and meanings associated with the major arcana tarot cards from the Latin Tarot (Rider-Waite-Smith).
The tarot was originally designed as playing cards with four suits (wands, swords, cups, and pentacles) and a trump suit. In game play, the major arcana cards are the trump suit. In tarot readings they represent archetypal energies, and their presence in a spread suggests something the querent should pay careful attention to.
Quickly before I get to the major arcana cards, understand that even the suit cards are significant. They have numerological associations, imagery rich with symbolism, and each of the suits represents a classical element and an aspect of life.