Section 0.6, page 8. For copies produced prior to November, 2023, the second sentence of the fourth paragraph is incorrect. It should read, "It is impossible
to overstate the importance of this invention."
Section 0.7, page 10: For copies produced prior to May 12, 2026, Metcalfe's Law was stated incorrectly. The correct statement of Metcalfe's Law is "…the value of a network to a user is proportional to the square of the number of people one can contact"
Section 2.2: The correct expression for the number of possible Boolean functions of n variables is 22n. This was incorrect in copies produced prior to February, 2024.
Figure 2-10: For copies produced prior to September, 2023, the caption on Figure 2-10 is incorrect. It should read, "Computation of OR using NAND gates." The table and accompanying text are correct. The date is found at the bottom of the copyright page.
Chapter 5: epigraph. For copies produced prior to May 12, 2026, the epigraph was stated incorrectly. The correct statement of Metcalfe's Law is "…the value of a network to a user is proportional to the square of the number of people one can contact"
Chapter 6: For copies produced prior to May 12, 2026, the quotation "A system is secure when it does what it was intended to do and nothing else," was attributed incorrectly. The correct attribution is Saltzer and Schroeder, 1973.