Beyond these aspects, the product, according to Gomes Son (2006), if characterizes for three functions. They are: Practical function can be understood as ' ' the adequacy of the product to the physiological necessities of the user in terms, for example: of use easiness, prevention of fatigue, offers of comfort, security and eficcia' '. (P. 43) Aesthetic function ' ' it is the psychological aspect of the multissensorial perception that has as main attribute the enjoyment of the beauty, the pleasure and contemplativo well-being in relation to data object, on the part of usurio.' ' (P. 43) Symbolic function if bases ' ' in the function aesthetic-deed of division of the product, in the dimensions semiticas' '. It is on, despite indirectly, to the practical function.
The symbolic function is disclosed by means of the style. (P. 44) the aesthetic function of the product, according to Norman (2004), can influence the individual how much to its form to think, thanks to the attractive object fact to provide welfare sensation, despertando the creativity. The emotions also can intervene with the form as the individual sees an object. Norman (2004) explains that a product presented with positive affective characteristics can be more pleasant to eyes of the consumer and that the form as the individual if relates with the product or with the mark they can be on to its previous experiences. When it has satisfactory sensation how much to the product, either it for the fulfilment of its functions, the performance or its usability, this product will be able to get success; in case that contrary, it will be predestinold to the failure. The same author still quotation that the differences of personality and behavior of the individual must be analyzed to if developing a product and that the products in its majority must be sensible to these differences.