IT consulting services; Design and development of computer software; Providing a website featuring technology which enables users to list goods for sale; Providing a website featuring technology which enables users to search and purchase goods for sale; Providing on-line non-downloadable software which enables users to list goods for sale; Providing on-line non-downloadable software which enables users to search and purchase goods for sale; Application service provider featuring application programming interface (API) software for integration of listings of goods for sale into websites; Providing on-line non-downloadable software featuring application programming interface (API) software for connecting information about goods for sale with a website; Providing application programming interface (API) software for integration of information about goods for sale into online software and websites