摘要:Maintenance of stocks in companies at an optimal level of effort has been since time immemorial. In the distant past businesses had to deal with the problem without any computer support which – in the present time – is indispensable. Inventory models for calculating optimal order quantities and reorder points have been in existence for a long time. Henry Ford was already aware of the degradation of financial resources bound in inventories and tried to answer key questions, i.e. When? and How much? Long before such systems as JIT, TOC and MRP were introduced, companies had been using other tools to manage their production and inventory.