designer's own words:M-card is mobile-housekeeping personal account book. The meaning of 'M' is money and manager. It considers waste of papers and financial management. As its title, which can be brought in a purse with its portability. It provides convenience for us and records all consumption-details instead of using paper-receipt. For living everyday life, we get a lot of receipt continuously and throw those away meaninglessly. As a result of it, there would be millions of receipt dumped out.It must be continued to spend a large amount of resources, otherwise we find out appropriate recipe for resolving this issue of paper waisting. Moreover we are using credit card much more than before and there is a problem, that has deferred payment system, so users should compute the amount asked. It makes users feel uncomfortable to manage themself. If we can manage the receipt effectively, we will be able to know our patterns of consumption, and consequently, correct our wrong consumptive habits. Moreover, we can set plans to control our economic life.