Introduction

Abstract

Taking the discovery of the “Ultra Rays”, nowadays called “Cosmic Radiation”, by Victor Hess 1912 as a begin, the research field of Astroparticle Physics celebrates in 2012 its 100th Birthday. It is a unique research field, to which results from a large number of other physical disciplines contribute and which treats fundamental questions of astrophysics, particle physics and cosmology. In this book, the development of Astroparticle Physics since its beginning in the early 20th century is described by contributions of authors who all have left their distinctive footsteps in the field they are reporting about. Emphasizing the basic ideas of the development, in this first chapter a tour d’ horizon on the connecting path between the following contributions is followed.