This quick-reference guide is ideal for teachers, students, and parents. The definitions are written in simple language that students will readily understand and find useful. Diagrams and illustrations are used to help reinforce and support the definitions. Definitions of science and technology terms are accompanied by illustrative support-including charts, graphs, and diagrams that add clarity and meaning. Facts on topics from the planets in our solar system to the accomplishments of scientists and inventors are included in ur comprehensive appendices.