Natural science subjects that involve a lot of measurement or model data require a correct, meaningful, and accurate application of statistical analysis methods. This is not only true for meteorologists and all geoscientists, who are the primary audience for this book, but it can also be successfully used by other natural scientists such as biologists, as well as in the social sciences and humanities. The author begins by introducing the general principles as well as the "philosophy" and challenges of statistics. This is done in an easily understandable manner, without assuming advanced mathematical knowledge. Furthermore, newer and more complex methods such as cluster analysis, EOF, neural networks, and various aspects of time series analysis are also covered, with references to further literature. Many examples, which are consistently straightforward, illustrate the concepts.