Materials and operations can be grouped so thus providing opportunities for convenient work with database and precise accounting of technological peculiarities for production costs calculations. Group is arbitrary set of united materials and operations by user decision.

E.g. it is possible to group used linear materials and create several subgroups: wood particleboard, fibreboard, MDF, etc. The same actions can be executed with accessories and two subgroups can be created: fasteners and decorative accessories. It allows to calculate prime-cost and take different material groups expenses into account. Here is the following example. Subgroups are created according to used material thickness for disk saw precise consumption normalization per one linear meter for wood particleboard.

Material and operation groups allow to control level of detail of expenditures calculation. E.g. it is possible either to account precisely saw degradation depending on material thickness or to ignore saw degradation dependence on material thickness and to use some kind of general consumption norm. It is possible for all the materials and operations.

Another method of materials and operations classification is to join them into classes. Class is a set that includes materials or operations united by the user. Groups and classes exist independently from each other. Materials joining into classes is used for document datasets creation and pricing peculiarities accurate accounting.

Principles of materials and operations classification can be very diverse, e.g. it is possible to join main usable materials in one class, auxiliary materials - into another, tool degradation - into third one. Operations can be joined into classes according to technological areas and departments for the purpose of work content specification and salary expenses value for separate areas and departments in particular product prime cost.