This book, written in a particularly readable and accessible style,stresses the fundamental ideas relevant to the understanding of the electricalproperties of materials. Topics are selected so that the operation of deviceshaving applications (or possible future applications) in engineering can beexplained.The mathematical treatment is deliberately kept simple: well within the grasp ofa second-year undergraduate student. This is achieved by choosing the simplestmodel that can display the essential properties of a phenomenon and thenexamining the difference between the ideal and the actual behaviour. For thisnew sixth edition, new or updated information is included on: Fullerenes; III-Vand II-VI semiconductors; High Electron Mobility Transistors (HEMTs):Photorefractive materials and semiconductor lasers; Optical fibre innovations;New magnetic materials; the Quantum Hall effect.The text remains a highly readable, comprehensive, and straightforwardintroduction to the electrical properties of materials.