Telepathy is the ability to communicate with others with the mind. Within the field of parapsychology this is considered to be a form of ESP. Most often telepathy occurs spontaneously in incidents of crisis where a relative or friend has been injured or killed in an accident. An individual is aware of the danger to the other person from a distance. Such information seems to come in different forms as in thought fragments, like something is wrong; in dreams, visions, hallucinations, mental images, in clairaudience, or in words that pop into the mind. Often such information causes the person, the receiver, to change is course of action, such as changing his travel plans or daily schedule, or to just call or contact the other person. Some incidents involve apparent telepathy between humans and animals.