www.howardism.org
Babblings of an aging geek in love with the Absurd, his family, and his own hubris.... oh, and Lisp.

Ada Lovelace

Ada Lovelace

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Her Family

  • Born 10 December 1815
  • Father was Lord Byron, a famous poet
  • Parents divorced as a baby
  • Mother was bitter
  • She wanted to protect Ada from her father’s “bad genes”

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Her Life

  • Mother pushed logic, rational thought and mathematics
  • Ada decided to combine math and art
  • She called it “poetical science”
  • She died of cancer at age 35

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Difference Engine

  • Friends with Charles Babbage
  • Built a prototype of a “Difference Engine”
  • Never actually built until 1991
  • Had plans to build an “Analytical Engine”
  • Essentially a mechanical computer

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First Programmer

  • Realized that number is a symbol
  • Numbers can be changed based on rules
  • Symbols could also be changed by rules

    Father + Mother = Child

Symbols

What does this mean?

1010100100010100011010010000000100001010

Split in Groups of 8

1010100100010100011010010000000100001010

  • 10101001
  • 00010100
  • 01101001
  • 00000001
  • 00001010

Convert to Decimal Numbers

  • 10101001 = 169
  • 00010100 = 20
  • 01101001 = 105
  • 00000001 = 1
  • 00001010 = 10

Numbers aren’t always Numbers

  • What if computer had some commands
  • Each command was numbered
  • Then any number could be either:
    • An actual number, or
    • A command

First Command

  • Assume first number is a command
  • Then 169 is command to “Load”

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Load a Number

  • “Load” says next number is a number
  • Loads 20 into the processor

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Next Command

  • Next number must be a command
  • 105 is the command to “Add”

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Add a Number

  • Commands says next number is a number
  • Adds 1 to the loaded number
  • Now 21 is the loaded number

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Multiply by Two

  • Next number must be a command
  • Called “multiply by 2”
  • Multiplies 21 by 2 leaving 42

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This is how a Computer Works

  • This is how computers work.
  • Our fancy instructions are just “abstractions”

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