Auras display the entire rainbow of colors, and respond to the emotional and physical status of the body. There are many people who interpret the colors they see for a variety of purposes. The colors might detect an illness or reveal an emotional issue, for example. However, different traditions disagree about the meanings of different colors seen. Therefore, the colors should be interpreted by the person who sees them, not by some "Mystical Dictionary of The Auric Spectrum".
Even if they cant be seen, auras can be felt. Hold your hands out about two feet apart, palms facing each other. Slowly bring your hands together until they are about 8 inches apart. Can you feel any changes? Slowly bring your hands closer until they are about 2-3 inches apart. At this point you should feel like two magnets are trying to slightly repel each other. (Have you ever played with magnets, and tried to get the wrong ends to match up? It's that sensation.) Bounce your hands together and apart along this "magnetic" zone and you can really feel the auras bouncing off of each other.
Once mastered, this technique allows a practitioner to work directly with the auric energy, most commonly for healing.
~Flame RavenHawk