Materials that are converted or processed to make the finished product. In category management in a manufacturing business, the most basic classification of categories is between direct and indirect materials. As direct materials are usually account for a greater share of total spend, and affect the quality of the final product, direct materials are usually seen as the more demanding of the two groups. Indirect spend includes stationery, printing, office supplies, pest control, telephone costs etc., while direct materials will be whatever is used to create the finished product. See also Materials, Indirect and Maintenance, Routine, Operating Categories.