The book is focused on regression models, specifically one-dimensional generalized linear models (GLM). It is intended primarily for students and colleagues of biology and requires only basic statistical knowledge, such as a one-semester course in biostatistics. The text of the book contains a minimum of statistical theory, but especially the solution of 18 real examples from biology. Each example is elaborated from the description and determination of the goal through the development of the statistical model to the end. The popular and freely available statistical software R is used for data analysis. The examples have been carefully selected to point out many problems and errors that may occur during data analysis. At the same time, they should motivate readers to think about statistical models and how to use them. The reader must try to solve the example himself on the data that comes with the book.