The subject and the goal of this final paper is to elaborate the theory of the e-business, and to show how it operates applied in practice in the firm Hrvatska Pošta d.o.o. (Croatian Post Ltd.). In this paper, the topic business on the Internet, and its developement is being dealt with. In short the creation, developement and devision of the e-business is being shown. Fields of appliance, devisions, advantages, disadvantages and models of this business are being described. Data recourses used in this paper are pieces of information and data from the specialist literature, academic articles and the scientific works. Besides the pieces of information and the data from the specalist literature, the work includes the data from the web page of the Croatian Post Ltd. In the preface there is the introduction, which describes e- model of business, which is also being discussed throughout the whole work. After the introduction, there is the second part where the theory of e-business is described, and how the technology influences the e- business, and what the advantages and what the disadvantages are of that kind of business. Summarised data is shown on the example of the firm Croatian Post Ltd., theory is connected with the example of that firm, and the way e.business is done within the big corporation system, respectively how the firm applies e-business, and what were the biginnings and have been the directions of e-business so far. The end of the work brings the brief conclusion of the theme.