The origin of the word biomagnetism is unclear, but seems to have appeared several hundred years ago, linked to the expression animal magnetism. The present scientific definition took form in the 1970’s, when an increasing number of researchers began to measure the magnetic fields produced by the human body. The first valid measurement was actually made in 1963, but the field began to expand only after a low-noise technique was developed in 1970. Today the community of biomagnetic researchers does not have a formal organization, but international conferences are held every two years, with about 600 attendees. Most conference activity centers around the MEG (magnetoencephalogram), the measurement of the magnetic field of the brain.