According to the DIN standard, usability or also user-friendliness of a product is 'the extent to which a product, system or service can be used by specific users in a specific application context in order to achieve specific goals effectively, efficiently and satisfactorily' (see DIN standard). The product designers at Siegelwerk know exactly what is important when designing a product in order to achieve the best possible user-friendliness and therefore a successful product.