Lexicon of Online and Distance Learning, a desktop resource, focuses specifically on distance education for researchers and practitioners. It provides key information about all levels of education (that is, K-12, higher education, proprietary education, and corporate training), allowing for comprehensive coverage of the discipline of distance education. The book offers a comprehensive index of distance learning terms; cross-references to synonyms and, when appropriate, online web links to encourage further exploration. Each lexicon entry is categorized by its root terminology-general, education, technology, instructional technology, or distance education-and provides the actual definition and complete exploration of the term along with specific references that include related books, volumes, and available manuscripts.