1. A data processing system for reducing an amount of data storage used to capture variations in a product structure, relative to storing each variation individually, by managing variations in a product structure for a product, the data processing system comprising: a processor; and a non-transitory computer recordable storage medium in communication with the processor and storing a model, the model comprising: a primary hierarchical organization comprising a group of domain master objects, a main structure, and a number of instantiated structures, wherein at least one domain master object in the main structure is associated with an instantiated structure in the number of instantiated structures, the group of domain master objects comprising a number of objects considered necessary in a product structure; and a number of optimized product variant structures comprising a group of domain configuration objects in which each domain configuration object in the group of domain configuration objects represents a configuration for a component represented by a corresponding domain master object in the group of domain master objects, wherein the number of optimized product variant structures is a number of secondary hierarchical organizations in which each secondary hierarchical organization in the number of secondary hierarchical organizations is associated with the primary hierarchical organization and configured to represent a variant of the product and wherein a number of domain configuration objects in the each secondary hierarchical organization represents a number of variations in the product structure for the product; and wherein the group of domain master objects and the group of domain configuration objects belong to domain classes derived from fundamental classes, wherein a domain master object in the group of domain master objects is selected from one of a domain definition object, a domain usage object, and a domain occurrence object, and wherein a domain configuration object in the group of domain configuration objects is selected from one of a definition configuration object, a usage configuration object, and a usage configuration object; and the processor configured to modify the non-transitory computer recordable storage medium by being configured to add a secondary hierarchical organization to the model for a new variant of the product and to nest the number of secondary hierarchical organizations within the primary hierarchical organization, whereby a first amount of data storage used to store the model in the non-transitory computer recordable storage medium is less than a second amount of data storage which would be used to store individually the number of variations in the model.