The father of computing history:
Charles Babbage
by Anja Jentzsch
[email protected]
Charles Babbage (1791 - 1871)
• born: 12/26/1791
• son of a London banker
• Trinity College,
• Lucasian Professorship
• Mathematician and
Difference Engine
• 1822
plan for calculating
and printing mathematical
tables like they were used in
the navy
• using the method of
difference, based on
polynomial functions
Difference Engine
• 1822
design 6 decimal places with secondorder difference
• 1830
engine with 20 decimal places and a
sixth-order difference
• 1830
end of work on the difference engine
because of a dispute with his chief engineer
Analytical Engine
• 1834
plans for an improved device,
capable of calculating any mathematical
• increase of calculating
• never completed
Analytical Engine - Architecture
• separation of storage and calculation:
– store
– mill
• control of operations by microprogram:
– control barrels
• user program control using punched cards
– operations cards
– variable cards
– number cards
Analytical Engine
• more than 200 columns of gear trains and number
• 16 column register (store 2 numbers)
• 50 register columns, with 40 decimal digits of
• counting apparatus to keep track of repetitions
• cycle time: 2.5 seconds to transfer a number from
the store to a register in the mill
• addition: 3 seconds
• conditional statements
Analytical Engine
First programmer – Ada Lovelace
• Ada Lady Lovelace, daughter of Lord Byron,
was working with Babbage on the Analytical
• first ideas of
– algorithm representation
– programming languages
• already realized:
– program loops
– conditional statements
Babbage’s meaning in history
• John von Neumann (1903 - 1957): universal
computing machine consisting of:
input / output
arithmetic/logic unit (ALU)
control unit
• based on Babbage‘s ideas
• 95 % of modern computers are based on the
von Neumann architecture
Babbage’s meaning in history
• Howard Aiken (1900 – 1973) developed the
ASCC computer (Automatic Sequence
Controlled Calculator)
– could carry out five operations, addition,
subtraction, multiplication, division and
reference to previous results
• Aiken was much influenced by Babbage's
• he saw the ASCC computer as completing
the task which Babbage had set out on but
failed to complete