XSP(1) When spelled xSP, a generic term for a service provider on the Internet, such as an application service provider (ASP), network service provider (NSP) or an Internet service provider (ISP).
(2) When spelled XSP, short for eXtensible Server Pages. The XSP language is a core technology of Cocoon, XML-based Web publishing in Java and one of the seven parts of the Apache XML Project. XSP is used to build dynamic XML content. It was originally created to allow Web authors to generate dynamic content without forcing them to learn a programming language. Because a Web document's content, style and logic are often created by different working groups or individuals, Cocoon aims for a complete separation of the three layers. Using XSP, content, style and logic are separated into different XML files using an XML DTD and are merged using XSL transformation capabilities.