Establishing, developing, updating, improving and adapting of data processing programs and/or data files (including multimedia, homepages and websites); granting of licenses in data processing programs, including computer and video games and data files; rental and leasing of data processing units, computer peripheral devices and programs for data processing, including computer and video games; operation of a network server for third parties; advisory services for computer hardware and software, advisory services for the organization and realization of data processing; rental of access times to databases; computer analyses; computer systems analyses; maintenance of computer software; documenting of image, sound and/or text data on machine-readable data carriers; drawing up and updating of homepages for computer networks