We live in a world of matter, which we experience as solid, and a world of forces, which act upon these solid things. But quantum physics is clear that what we call solid matter is composed of oscillating matter wave packets, and what we call forces are composed of oscillating energy wave packets. In reality, everything is composed of oscillating wave packets of one type of another. Scientists have long puzzled over force field phenomena that do not fit the four known forces: electromagnetic, gravity, weak and strong forces. These force field that do not fall into the classical four are sometimes labeled "subtle energies." They are called "subtle" because they cannot be observed or measured by any known instrumentation.

The transmission of electrical energy through wires, the broadcasting of radio signals and the phenomenon of visible light are examples of electromagnetic fields (EMF). EMF always consists of both an electrical field and a magnetic field. It occurs in a wide range of frequencies, spanning what is called the electromagnetic spectrum. At the high end is cosmic radiation. At the low end is household electricity. The lower electromagnetic frequencies have been utilized by man to generate electricity and all associated electrical products, including all electronic communication systems and electrical appliances. Electromagnetic radiation (EMR) is often called an electromagnetic field (EMF) when it falls within the lower frequencies. Both EMR and EMF are commonly used to mean the same thing.

Electricity is the most common source of power throughout the world because it is easily generated and transmitted to where it is needed. As electricity moves through wires and machines, it produces EMF. The power grids of nations consist of electrical generation, transmission and distribution facilities. As electricity is sent along the wires of the power grid, EMF is created. In cities, primary electric power distribution lines run across the top of utility poles and feed secondary transformers, which are then connected to the electric power meters of buildings. Once electricity is delivered to the user, it continues to produce EMF throughout the wiring systems of offices, homes, schools, factories and other structures. The appliances and electrical equipment connected to these wiring systems produce their own EMF as well. In the workplace the generators of EMF include computers, cell phones, fax machines, copy machines, fluorescent lights, printers, scanners, telephone (PBX) switching systems, electrical instruments, motors and other electrical devices. In homes, the immediate sources of EMF include electric blankets, electric water bed heaters, hairdryers, electric shavers, television sets, stereo systems, air conditioners, fluorescent lights, electric can openers, telephone answering machines, cell and portable phones, refrigerators, blenders, portable heaters, clothes washers and dryers, coffee makers, vacuum cleaners, toasters, and microwave ovens.  EMF is not only produced by electricity moving through wires or machines, but it is the nature of all television and satellite transmissions, as well as radio and microwave communication systems, including cell phones. Transportation methods such as automobiles, trucks, airplanes, electrical and magnetic trains and subway systems are significant sources of EMF. More than one source of EMF in proximity to other sources will produce overlapping fields in the same area. Any metropolitan home or office environment in the world will be saturated by a variety of interpenetrating EMF from a variety of sources. The nature of EMF is very complex and the number of EMF sources are rapidly growing.