This book discusses the basics of working with KOMPAS-3D. It is based on three large practical examples, during which the basic techniques for developing three-dimensional models of parts and assemblies, associative drawings and specifications are mastered step by step. Additionally, an example of using the KOMPAS system for 3D modeling and restoration of drawings of samples of equipment of historical value is given. As a sample, a three-dimensional geometric model and associative drawings of the assembly and parts of the unguided rocket M-13 (the famous Katyusha) and the specification are shown.The book discusses the elements of the system interface and the types of documents with which the system works. The issues of exporting and importing files are considered.It should be noted that regardless of the changes that have occurred in the KOMPAS-3D interface in the process of changing versions, the methods of work remain the same for all specified versions. With the advent of new versions of the program, its functionality only increases.(The CD is included only with the printed edition.)