Lecture Notes: Evolution of Computers During World War II

Introduction

• Theme: War mobilizes science and technology.
• Historical Example: Leonardo da Vinci working for Caesar Borgia in 1500.
• World War II Impact: Not just weapon systems, but crucial advancements in computing.

Bletchley Park and Codebreaking

• Location: Bletchley Park, England.
• Objective: Break the German wartime Enigma code.
• Recruitment: Mathematicians and thinkers, tested via crossword puzzles (Daily Telegraph).

German Enigma Coding Machines

• Function: Encrypt messages using rotaries.
• Challenge: Germans frequently changed encryption settings.
• Breakthrough: Polish capture of an Enigma machine.

Key Figures and Contributions

Alan Turing

• Significance: Led efforts in codebreaking at Bletchley Park.
• Conceptual Work: Invented the "Turing Machine" as a thought experiment to determine computability.
• Contribution: Designed machines to break German codes.

Tommy Flowers

• Work: Created new machines using vacuum tubes in "Hut 11" at Bletchley Park.
• Innovation: Developed Colossus, an electronic digital machine.

Development of Colossus

• Function: Used 1,500 to 2,400 vacuum tubes.
• Achievement: Broke German codes before D-Day, aiding in the Allied success.
• Limitation: Not a "Turing Complete" machine; special-purpose only.

Defining the First Computer

• Criteria for a Modern Computer:
  • Digital and binary (uses on/off switches).
  • Electronic (not purely mechanical).
  • General-purpose.

Conclusion

• The ENIAC: Considered the first computer by the criteria outlined.
• Contributors: John Mockley, Jean Bark, and others at the University of Pennsylvania.

Reflection

• The evolution of computing technology was significantly shaped by the needs and innovations during World War II.
• The collaboration of brilliant minds like Alan Turing and Tommy Flowers played a pivotal role in the development of early computers.
• The quest to define what constitutes the "first computer" depends on specific defining characteristics.