Java API for XML Processing (JAXP) is a set of Java-based APIs that provide support for processing XML documents in Java applications. JAXP includes standard APIs for parsing, transforming, validating, and manipulating XML documents, making it easier for developers to work with XML in their Java applications. It also includes support for several XML-related technologies, such as XSLT, XPath, and SAX. This skill is useful for developers who work with XML documents and need to incorporate them into their Java applications.