Charles Babbage, Ada Lovelace, J. Presper Eckert, John Mauchly, Kay Mauchly, Konrad Zuse, John von Neuman, Alan Turing
The difficulty
of computation
Many areas depend on computation - science, engineering,
navigation, etc. The computations needed by these areas were for
many years performed manually by people called
"computers". Manual computation is slow, laborious and
fraught with mistakes. Try to get a feel for the difficulties by
paying close attention to Babbage’s and Kay Mauchly’s
description of the difficulty of producing various kinds of
mathematical tables.
Kay Mauchly prepared firing tables for the U.S. Army. The following excerpt from James Burke's The Pinball Effect: How Renaissance Water Gardens Made the Carburetor Possible (pg. 200) points out the difficulty of computing shell trajectories:
When any weapon fires, many factors interact to influence the accuracy with which the projectile reaches the target. These factors include a truly mind-boggling number of considerations: type of gun, type of shell, type of propellant, type of barrel, rate of propellant burn, type of primer, type of cartridge case, pressure of gases in the barrel, pressure of back shock, projectile velocity, friction created by the shell leaving the barrel, gun-barrel bore, barrel distortion from the heat of the explosion, density of the air, near-muzzle-blast-absorption system, resistance on the shell in flight, forebody drag on the shell, shock waves created by the shell, shell-skin friction, shape of the shell, angle of trajectory, rate of shell spin, shell mass, ambient air temperature, wind direction and speed, humidity, force of gravity, relative height of target, impact type required, target penetration required and impact angle.
The tables made up to help gunners account for all of these factors were produced by the mostly women mathematicians at the Ballistic Research Labs in Aberdeen, Maryland. Burke (pg. 201) explains:
Their task was daunting in the extreme. A typical single trajectory required 750 multiplications, and a typical artillery table for one gun included over three thousand trajectories. Working round the clock, with the mechanical calculators then available, the mathematicians at Aberdeen took thirty days to complete one table. By 1944 requests would be arriving at the lab for six new tables a day.
If you would like to see how firing tables were constructed read Harry Reed's account of working with ENIAC to compute ballistic firing tables.
A Universal
Machine
Several times throughout
the tape people describe the computer as a universal machine.
A universal machine is a machine whose purpose is not
predetermined when it is built. A universal machine can be
instructed to carry out widely diverse tasks.Computers get their
instructions through programs. Be on the lookout throughout these
tapes for descriptions of the trails and tribulations of writing
computer programs.
Evolution of
Computing Systems
The narrator in the tape
says that computers became "smaller, cheaper, and better
faster than any other technology in history" and " in
just 45 years the computer has permeated almost every aspect of
modern life". For this evolution to happen three things were
necessary - the switching and other hardware elements
had to become cheaper, smaller and faster, programming had
to become easier, and the machine’s software had to
become more useful and user-friendly. As you watch the tapes keep
hardware, programming, and software in
mind. Watch for the important hardware and software developments
that make this evolution possible.
Computers as
Giant Brains
In the U.S. early
computers were built primarily to do numerical computation. In
England the earliest computers were used to break codes during
World War II. This experience lead people like Alan Turing to
consider other uses for computers, uses that required symbol
manipulation rather than number crunching. Turing thought that
machines could "carry out any task that can be described in
symbols". In particular, Turing views intelligence as a
formal or computational system. A formal system has a set of
symbols and a set of rules that can be used to manipulate the
symbols to form new symbols. The two formal systems that most
people are familiar with are arithmetic and logic. Arithmetic has
a set of symbols (numbers and operators) and a set of rules
(addition, subtraction, etc.) for manipulating the symbols. This
computational view of intelligence has greatly influenced current
and past AI (artificial intelligence) researchers.
The Downside of
Computing
You will find a concern for how people are affected by
computers throughout this series of video tapes. The tapes
discuss both the advantages and disadvantages of computing. The
disadvantages most of us are aware of have occurred in the
workplace. This concern is foreshadowed by the narrator’s
statement that "offices full of clerks would be replaced by
a single machine". Be on the lookout throughout the tapes
for situations where people are adversely affected by computers.