The book presents an approach to parallel programming taking into account modern realities. Information is structured in such a way that it is easily assimilated, even if the reader does not have special knowledge. The general principles of writing parallel and asynchronous code are considered; the implementation of data parallelism is shown in short and simple examples. At the end of the chapters, questions are given to repeat the past. The publication is intended for C # programmers who want to learn the concepts of parallel programming and multithreading, and then use the knowledge gained for applications based on .NET Core. It is also useful for specialists who want to familiarize themselves with the principles of parallel programming on modern equipment.