An electron emission display includes first and second substrates facing each other to form a vacuum envelope, an electron emission unit formed on the first substrate, and a light emission unit formed on the second substrate. The inputted bill data and bill format data are then stored in a first area of the bill presentment and payment database. This removes the need to form ink supply channels with complex geometries such as pinch points and baffles in order to have the required hydraulic resistance to reverse flow. The presumed sensor position that corresponds to the set of reference points that most closely match the location of the identified distinctive feature is then presumed to estimate the actual position of the sensor. Thus, an oxygen source, which cannot be obtained in a human body, can be easily supplied to the fuel cell, and the fuel cell has higher performance than a fuel cell in which air is used as an oxidizing agent. A memorize feature may also be provided to permit handsets and other objects exchange information by wireless transmission.