150 years ago, in 1869, D. I. Mendeleev and L. Meyer independently published their ideas on the arrangement of the chemical elements in a periodic system. The United Nations and UNESCO therefore declared 2019 the International Year of the Periodic Table. The question arises, what is so special about this simple table? Join the author on a short journey to the history of the periodic table. Learn about its predecessors and look at how the periodic table of elements has evolved over the years. Discover the periodic properties of the elements. Learn what makes the periodic table so interesting and timeless, and see what other ideas there are and have been for representing it. The Author: Torsten Schmiermund has been working as a chemical technician in the chemical industry for many years.