Mediums are people, usually psychics, who have the ability to facilitate communication between the the spirits of the dead and living human beings, a practice that is known as mediumship.
Since the early days of human existence, people have had an interest in communicating with the dead, as might be suggested by cave drawings depicting skulls, bones, spirits and the afterlife. The biblical Witch of Endor was a medium who raised the spirit of the deceased prophet, Samuel. Interest in communicating with the dead peaked during the 1800s when seances and ouija boards became popular among the upper classes, then investigations revealing widespread fraud led to a loss of credibility.
However, some of those who investigated claims of spiritualism during this period became converts. These included Robert Hare, William Crookes, Alfred Russel Wallace, Pierre Curie, and Arthur Conan Doyle.
Today, although the established sciences do not consider claims of mediumship to be valid, there are still many people who practice mediumship, and many more who believe in the product of psychic mediums.
There are several variations in the practice. One form is similar to channeling, in that the spirit of the dead person takes control of the medium's voice and uses it to relay a message to another person, generally a family member or loved one. In other cases, the medium hears or otherwise becomes aware of the message and passes it on.
Other forms include materializations of the dead person or the presence of his or her voice, or telekinetic activity.
Communication with the dead is associated with several belief systems, including Vodun, Voodoo, Spiritism, Spiritualism, Umbanda, Candomblé, and some New Age groups.
Within Spiritualism, the medium enters a trance, in which she or he facilitates communication through automatic writing or drawing, as well as through various telekinetic means, such as knocking, rapping or ringing a bell.
Mental mediums communicate with the dead using telepathy, which may include clairaudience, clairvoyance, or clairsentience.
Most trance mediums remain conscious during the period of communication, although the spirit may use the medium's mind or voice in order to communicate.
Physical mediums are those through which the spirit of the dead use physically perceptible means of communications, such as raps on a table or other noises, voices, materialized objects, manifestations, and so on, purportedly using the medium as a source of power.
In some cases, direct voice communication is used, in which the spirit speaks independently of the medium. As trumpets are sometimes used to amplify the signal, direct voice mediums are referred to as trumpet mediums.
Channeling might be considered a form of mediumship, but it is covered in its own parallel category.
 
 
Recommended Resources
Andrew Anderson, Psychic Medium
Born in Los Angeles, Andrew moved to Illinois in 1994, and currently resides in the Chicago region. Over the years, he has worked with police departments and others in solving murders and other crimes, and has made public appearances as well as guest spots on various radio shows. Price listings for readings in person or by phone are posted, as well as for emergency readings and email responses. Client testimonials are presented, and his books are also offered for sale online.
http://www.psychicmediumreading.org/
On this site, Bob Olson, the host of Afterlife TV and former skeptic, lists psychics and mediums that he has vetted and considers to be legitimate. An overview of the 15-point test used to vet mediums is set forth, and the list includes contacts, website links, case profiles, client testimonials, video, and other information. A schedule of programs and events, a list of related books, and media packets are included.
http://www.bestpsychicmediums.com/
Situated in Orlando, Florida, Heidi specializes in medium readings and psychic readings, by telephone, Skype, or in person at her office. Her expertise is discussed, along with a brief biography, and an overview of her services and policies. Client testimonials, pricing and scheduling information, a schedule of events, and online bookings are included. A blog offering general information about psychic readings and mediumship is also available.
http://www.heidithemedium.com/
Jennifer is a psychic medium, profiler, author, seer, and medical intuitive who has been profiled on Dr. Phil, and has been a reoccurring guest on the Ricki Lake show. Biographical and professional information is set forth, including her memberships. Other resources include her work with law enforcement and families on missing person cases, cold cases, and unresolved deaths, as well as her other services.
http://www.jennifershaffer.com/
Joanne Gerber is a psychic medium and spiritual teacher from Boston, Massachusetts. Her site offers a description of the spirit world and an overview of the services that she offers, including her availability for readings, classes, workshops, lectures, and demonstrations throughout the United States. A calendar of events and video of her media appearances, press releases, and contacts are posted, along with gift certificates and a chat room.
https://www.joannegerber.com/
The medium, author and lecturer is one of the most famous psychic mediums in the United States, given his popular television show, Crossing Over, the first syndicated television show devoted to psychic mediumship. His site features a calendar of events, newsletter, and a store where books, DVDs, and other items may be purchased. Through his site, interested people can sign up for private or group readings, workshops and classes.
https://www.johnedward.net/