This four-volume reference explains mathematical concepts and provides a historical overview of the field in language appropriate for middle school through high school students, or for general readers. Separately indexed, each volume is about 220 pages and devotes 35 pages or so to an identical glossary and topic list probably a useful feature for student readers who might not make the effort to refer to a separate volume. Entries are alphabetically arranged and discuss topics related to the uses and effects of math in daily life; its role as a tool for measurement, data analysis, and technological development; important people; and careers. Each entry is signed and includes a brief bibliography. Entries range from a half page to several pages and are abundantly illustrated.