Catalogues of parts and assembly units of tractors, trucks, buses, harvesters, machines and engines are reference technical manuals, designed to identify the units and details the specific vehicle that is essential, both in their buying and selling, and the calculation and compilation of requests for spare parts. Catalogues can also be used to familiarize themselves with the equipment and vehicle construction, the order of disassembly and assembly of components and assemblies. Modern electronic catalogs (e-catalogs) – this electronic version of the well-known to all directories, books, parts and assembly units of tractors, trucks, buses, harvesters, machines and engines. They contain extensive database and using the special built-in programs allow you to easily and quickly obtain accurate information about the required spare parts, including information on their appearance, original number, common name, location, etc. Futurist is full of insight into the issues. installation of E-catalogs are, in fact, computer reference books with information about all the elements of machines – from large components and assemblies to the smallest details of their codes (common catalog numbers), names, graphics (drawings, paintings), with interactive map of every detail in the specification. All these directories have the inherent compactness of the computer programs, high-speed information retrieval, extensive, stunning clarity and ease of use. Any of the directories contains illustrations from the list of parts and assembly units, which for convenience grouped in the specification. As is known, the specification is the basic design document, a text document that defines the composition of products, consisting of two or more parts. Therefore, if we take hence information, refer to the name and other identifying information of parts and components will meet ofitsialinym and are generally accepted.