The built-in programming language of the 1C: Enterprise 7.7 package, methods for configuring and configuring the system using it are described. Additionally contains the required minimum of information about object-oriented programming and database theory. The book is written in an accessible language, the presentation of the material is based on relevant and useful examples. The full range of tasks encountered in practice is considered: from making small changes to creating your own configuration. The publication is intended not only for programmers or system administrators, but also for accountants, economists, managers and other specialists who plan to make configuration changes without assistance.