Preface

　　　An accident occured in the Fukushima Nuclear Power Plant Reactorl dueto the Great East Japan earthquake disaster that happened on March 11,2011. Afterwards,there was an interview with Tokyo Electric company where they said radioactivity had begun to leak from the nuclear power plant. The people felt worried about the invisible radiation and radioactivity, and came to be curious about methods to protect themselves.

　　　What is radiation? How does radiation effect our life? What should we do to protect ourselves from radiation? On this site, I'll explain there things clearly. I think we shouldn't be afraid too much and cope excessively becouse it is invisible. So, let's understand radiation properly so we can live a life of safety and security?