Multifunctional periodic system of chemical elements, the best PC implementation of this well-known system. It provides an exhaustive information on each element (more than 30 data types for each chemical element) and special built-in calculator to balance the most complicated chemical equations. The program offers a lot of extended features such as supporting Datenbank of chemical reactions, producing variety charts of different properties of chemical elements, illustrating metal activity series and giving more then 20 different presentations of the periodic system of chemical elements.