1200-1800: The introduction of mechanical aids
1800-1895: The introduction of the telegraph, the telephone, and mechanical computing aids
1895-1939: The introduction of radio stimulates new applications
Mid-1930s-1950: World War II accelerates developments in all fields
1950-1969: The introduction of solid-state electronics and satellite technologies
1970-2003: Extended networking concepts bring closer integration to all three technologies
Appendix A: Introduction to cryptology
Appendix B: The origins of NSA.
