Healers, as one would assume, heal people. This power of theirs comes from inside them; you are born with or without it, and while you can learn to control it you cannot be given the gift or take it from another person. Each healer goes to school, and is trained by a mentor of sorts.
All healers have the same talent; they knit together bone, shrink tumors, and flush the fluids from your body, but the power of each individual healer is different.
It should be known that healers aren’t miracle workers; the sicknesses they cure don’t simply disappear. If anything, Healers simply speed up the healing process that comes naturally for the body. Healers talk to your body as they mend it, they tell the blood to clot or thin; it is said to be a mixture if telepathy, telekinesis, and other skills that have yet to be named.
A good example of the less glamorous side of healing is in Roadkill (pg. 149), when Rafferty cures Cal of viral pneumonia. The liquid that was in his lungs had to go somewhere, it just happened to come up in an unpleasant manner. Rafferty says it’s like your lungs vomiting instead of your stomach, Cal agrees with his description.