Encyclopedia or encyclopaedia (from Gr. enkyklios paideia, meaning comprehensive education) and originally signifying instruction in all branches of knowledge, or a comprehensive education in a specific subject. This concept gave rise to the idea of collecting the materials for such instruction into a single work, in which the contents and relations of the various arts and sciences would be explained systematically. Attempts to produce books of this kind were made more than 2,000 years ago, although the name encyclopedia was not given to such works until the 16th century. Continued