Today′s e-business consists largely of interactive marketplaces and portals which offer services to their customers. Especially in the field of Business-to-Business (hereafter referred as to B2B) commerce vertical and horizontal interoperability between the heterogeneous IT systems and platforms of trading partners are essential for business endeavours in order to automate transactions and to cut costs respectively. [...] The intention of this paper is to show how schema languages emerged from the need of interoperability and how they solve many challenges presented by e-commerce requirements. Furthermore the ideas and philosophies behind two significant schemas for XML, the XML Schema and RELAX, are highlighted and contrasted against each other and against the intention of DTDs. The question to be answered is whether XML Schema can compete against alternative schemas in the long run and whether it can still become a widespread standard within the rapidly growing e-commerce environment. The main part of this paper is divided into four core parts. The first section will give the reader an overview about the current e-commerce needs and requirements, followed by a critically evaluation of DTD (Document Type Definitions) and XML (Extensible Markup Language) as considerable options to attempt meeting the e-businesses requirements presented earlier. The next section will introduce a recent advance in XML technology, the Schema language, whose contribution and utility for e-commerce will be highlighted. In particular XML Schema as the W3C recommendation will be evaluated and critically compared with its significant competitor RELAX in the fourth section. The last part comprises a critically discussion about the schemas′ potential of becoming an enterprise-wide standard for XML document description. The end of this paper constitutes a summary of the results presented and conclusions drawn.
