(1) Binary system. Von Neuman was the first to suggest the use of a binary
numbering system represented by only two digits (0 and 1) to build computers, rather
than the 10 digits (0 to 9) of the decimal system. He suggested that equipment design
lent itself to the binary system since electronic components are either "on" or "off,"
conducting or not conducting, magnetized or not magnetized. Thus, computer
instructions could be coded as numbers and stored internally in the machine along with
data.
(2) Data and instructions stored together. The storage of instruction
programs with data in the same memory unit made it possible to arithmetically modify
instructions in the same way as data.
(3) Alterable instructions. Alterable instructions provided the capability to
alter instructions, as needed, during a computation to make them behave differently.
(4) Conditional control transfer. Conditional control transfer was a type of
machine instruction that permitted the program sequence to be interrupted and
reinitiated at any point.
conditional control transfer: a machine instruction that transfers control to a
designated instruction if some condition is true and continues in sequence to the
next instruction if the condition is not true.
(5) Programs in the subroutine library. With this innovation, frequently used
subroutines did not have to be reprogrammed for each new problem, but could be kept
intact in libraries and read into memory when needed. Thus, much of a given program
could be assembled from the subroutine library.
library: a collection of statement routines or executable programs, normally
residing on disk, that may be readily accessible for use by a computer. Most
systems have several libraries.
(6) The memory an assembly place for instructions. The all purpose
computer memory was like the assembly place in which parts of a long computation
were stored, worked on piecewise, and assembled to form the final results.
(7) Control as assembly place. The computer control served as an errand
runner for the overall process.
(8) Read and write memory (RAM) is designed to provide almost constant
access to any particular piece of information. Contents can be retrieved and altered by
the user at will.
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