Book excerpt: Online education, both by for-profit institutions and within traditional universities, has seen recent tremendous growth and appeal - but online education has many aspects that are not well understood. The SAGE Encyclopedia of Online Education provides a thorough and engaging reference on all aspects of this field, from the theoretical dimensions of teaching online to the technological aspects of implementing online courses—with a central focus on the effective education of students. Key topics explored through over 350 entries include: · Technology used in the online classroom · Institutions that have contributed to the growth of online education · Pedagogical basis and strategies of online education · Effectiveness and assessment · Different types of online education and best practices · The changing role of online education in the global education system