New edition of Polish Safer Internet Centre's compendium for parents and professionals working with adolescents is a glossary on the most present issues connected to children and youth's internet safety. The main goal of the compendium is to systematize current knowledge on children and youth activity online. In the compendium reader will find an diagnose of current social phenomenon taking place online, analysis of risky behavior with special consideration of causes and ways to prevent threats. The teacher or parent will find wide spectrum of educational and preventative guidelines.