The authors present a broad overview of time and frequency technology, particularly those trends relating to the generation and distribution of time and frequency signals. The authors provide a general look at these trends. They refer the reader to other papers, particularly to those in this issue, for greater detail. The topics considered are: background, including accuracy and stability, frequency standards, time transfer systems, and network synchronization; time generation, including various types of atomic clocks and quartz oscillators; and time distribution, including applications of time transfer concepts and practical synchronization limits. The characterization of components and systems is also addressed. >