All populations are now being exposed to varying degrees of man-made sources of electromagnetic fields (EMFs) and the exposure levels will likely continue to increase as technological inventions advance. EMFs are thus becoming a major health concern and generate intense debate within the scientific community and in the fellow citizens. Man-made EMFs are currently created mostly by mobile phone communication systems and broadcasting transmitters. Therefore, we provides an overview of the operating principles of electromagnetic field, and discusses the mechanism(s) underlying the effect. Additionally, we review EMF interaction mechanisms with biological systems, deals with the different effects of EMFs.