Humans live and breathe every day in an environment full of natural and artificial radiation. Radiation's nature is energetic particles and/or electromagnetic waves. The damage to tissue from ionizing radiation is being studied decades ago. In contrast, concerns, about the potential health risk associated with unprecedented exposure to non-ionizing radiation, emerge nowadays. Scientists expect objective results to be revealed after few decades of extended use of many low frequency devices or equipment, as well as wireless net and mobile phones. This paper reviews the sources and the most recent results of the effects of radiation, focusing however on the non-ionizing part and, especially, the radiation from radio waves and mobile phones.