Coronavirus, AIDS, and Ebola: Viruses are normally defined as pathogens. Most viruses are, however, not enemies or killers. Well-known virologist and cancer researcher Karin Moelling describes surprising insights about a completely new and unexpected world of viruses. Viruses are ubiquitous, in the oceans, our environment, in animals, plants, bacteria, in our body, even in our genomes. They influence our weather, can contribute to control obesity, and can surprisingly be applied against threatening multi-resistant bacteria. The success story of the viruses started more than 3.5 billion years ago in the dawn of life when even cells did not exist. They are the superpower of life. There are more viruses on earth than stars in the sky. Viruses are everywhere. Some of them are incredibly ancient. Many viruses are hundredfold smaller than bacteria, but others are tenfold bigger and they were discovered only recently — the giant viruses, even deep within the permafrost where they were reactivated after 30,000 years. The author talks about a completely new world of viruses, which are based on the most recent, in part her own research results. Could viruses have been our oldest ancestors? Have viruses even "invented" social behavior, do they lead to geniuses such as Mozart or Einstein — or alternatively to cancer? They can help to cure cancer. In this book, the author made a clear distinction between what is fact and what is her vision. This book is written for a general audience and not just for the experts. Its aim is to stimulate thinking, and perhaps to attract more young scientists to enter this field of research. This revised edition is brought up to date by a new chapter on the SARS-CoV-2 pandemic.