
THE EDUCATRON OF A COMPUTER
Grace Murray Hopper
Remington Rand Corp.
While the materialization is new, the idea
of mechanizing mathematical thinking is not new.
Its lineage starts with the abacus and descends
through Pascal,Leibnit% and Babbage. Fore
immediately, the ideas here presented originate
from Professor Howard K. Aiken of Harvard
University, Dr. John W. Nauehly of Eckert-
Hauchly and Dr. H. V. Wilkes of the University
of Cambridge. From Professor Aiken came, in
1946, the idea of a library of routines
described in the Hark I manual~ and the concepts
embodied in the Hark III coding machined from
Dr. Hauchly, the basic principles of the "short-
order code" and suggestions, criticisms, and
untiring patience in listening to these present
attempts; from Dr. Wilkes, the greatest help
of all, a book on the subject. For those
of their ideas which are included herein, I
most earnestly express my debt and my
appreciation.
Introd~Qtion
To
start at the beginning, Fig. I
represents the configuration of the elements
required by an operation: input to the
operations; controls~ even if they be only
start and stop; previously prepared tools
supplied to the operation I and output of
products, which may, in turn, become the
input of another operation. This is the basic
element of a production lines input of raw mate-
rial% controlled by human beings, possibly
through instruments~ supplied with machine
tools; the operation produces an automobile,
a rail~ or a san of tomatoes.
The armed services, government, and
INPUT
I CONTROL
~--'~OPERATION ~--~
industry are interested not only in creating
new operations to produce new results, but
also in increasing the efficiency of old
operations. A very old operation, Fig. 2?
is the solution of a mathematical problem.
It fits the operational configuration: input
of mathematical data~ control by the
mathematician~ supplied with memory, formulas,
tables, pencil? and papers the brain carries
on the arithmetic, and produces results.
It is the current aim to replace, as far
as possible, the human brain by an electronic
digital computer. That such computers
themselves fit this configuration may be seen
in Fig.
3.
(With your permission, I shall use
UNIVAC * as synonymous with electronic digital
computer; primarily because I think that way?
but also because it is convenient.)
Adding together the configurations of the
human being and the electronic computer? Fig.
4 shows the solution of a problem in two
levels of operation. The arithmetical chore
has been removed from the mathematician, who
has become a programmer, and this duty
assigned to the UNIVAC. The programmer has
been supplied with a "code" into which he
translates his instructions to the computer.
The "standard knowledge" designed into the
UNIVAC by its engineers, consists of its
elementary arithmetic and logic.
This situation remains static until the
novelty of inventing programs wears off and
degenerates into the dull labor of writing and
checking programs. This duty now looms as an
imposition on the human brain. Also, with the
computer paid for, the cost of programming and
the time consumed, comes to the notice of vice-
presidents and project directors. Co,son sense
dictates the insertion of a third level of
operation, Fig. 5.
OUTPUT
* Registered trade mark.
TOOLS
Fig. I -
AN
OPERATION
Fig, 2- SOLUTION OF
J PROBLEM H
PROBLEM
MATHEMATICIAN I
J
BRAIN
~-~
T
FORMULAS
TABLES
RESULTS
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