Sources such as dictionaries and encyclopedias are good starting points for obtaining basic information about issues, events, and concepts in the field of mathematics.
World of Mathematics
General Collection QA5 .W67 2001
Two volume guide to topics in mathematics. It includes theories, definitions, discoveries, concepts in the history of mathematical science. The volumes also include biographical entries on the most influential mathematicians from antiquity to the present. Its broad scope -- more than 1,000 narrative entries -- is organized alphabetically in a convenient encyclopedic format