From Relays to Electronic Computers
Z3 and Relays: Computing before Fully Electronic Machines
Distinguish digital representation from electronic implementation and understand relays.
In this lesson
Lesson goals
Distinguish digital representation from electronic implementation and understand relays.
The idea explained
A relay uses electricity to move a physical switch. Collections of relays can implement operations on binary representations. Konrad Zuse completed the relay-based Z3 in 1941. This separates two ideas: digital describes representation, while electronic describes implementation. Mechanical movement limits switching speed and introduces wear, helping explain the later importance of electronic switching.
Dates and milestones
- 1941: Completion of the relay-based Z3.
Why was this a turning point?
Programmable automatic operation could precede fully electronic hardware; architectural ideas and components evolved together.
Activity: try before reading the answer
A lamp controlled by a mechanical switch represents 0 and 1. Is the representation digital? Is the switch electronic?
Answer and explanation
The two-state representation is digital, but the switch remains mechanical even though electrical energy is used.