Abstract
This paper attempts to bring up to date the information on fundamental properties of silicon and germanium. Much the same topics are covered as in the author's earlier article "Properties of Silicon and Germanium" (henceforth referred to as I), which appeared in the 1952 Transistor Issue of PROCEEDINGS. Also included is some of the detailed knowledge on the band structure which has been obtained since 1952. This is essential to the understanding of many of the properties of these materials.