Diverse systems of codification exist: in the Alphabetical System, the materials are codified in accordance with the letters of the alphabet; in the Alphanumeric one, the possibility to combine letters and numbers, makes possible a bigger flexibility in the data; already the numerical system, possesss enormous amplitude, also having important variations, amongst which if it detaches the Federal American System (SUPPLY CLASSIFICATION). (DAYS, 2010, P. 190).

However, the system more used by the companies, is the System Decimal and the system of bar code that will be exemplificados to follow. 4,1 System Decimal Using the example of Days (2010), imagines that a company uses a classification that specifies the diverse types of products in the supply: 01? raw material 02? oils, fuels and lubricant. 03? products and process 04? finished products 05? products clerical. It is verified that all the products are codified in accordance with general headings, reflecting the characteristics of each one. After that each product is made a subdivision individualizando. For example: 05? products clerical 1? penxses 2? paper 3? ruler 4,1 Systems of bar codes In the current context of the administration of supplies, new tools come being used of form each more intense time, mainly for the great companies who possess a bigger dependence of more efficient and rigorous systems of information.

Systems ID and ERP are example of management systems that possess a bigger precision in the information, this fact potencializa the rationalization in the managemental decisions (RIBEIRO, 2010). Amongst these, the System of Generation of Bar codes? SGC, possess an including applicability, for allowing that products with different characteristics, forms, purpose etc.