Power lines, electrical wiring, and appliances all produce electric and magnetic fields.
EMFs are invisible lines of force that surround any electrical device.
Electrical and magnetic fields have different properties and possibly different ways of causing biological effects. Even though electric and magnetic fields are present around appliances and power lines, more recent interest and research have focused on potential health effects of magnetic fields. This is because epidemiological studies have found associations between increased cancer risk and power-line configurations which are thought to be surrogates for magnetic fields. No such associations have been found with measured electric fields. Impair sleep and learning, Altpeter et al.