Page "ENIAC" Paragraph 21

ENIAC was a one-of-a-kind design and was never repeated.

The freeze on design in 1943 meant that the computer design would lack some innovations that soon became well-developed, notably the ability to store a program.

Eckert and Mauchly started work on a new design, to be later called the EDVAC, which would be both simpler and more powerful.

In particular, in 1944 Eckert wrote his description of a memory unit ( the mercury delay line ) which would hold both the data and the program.

John von Neumann, who was consulting for the Moore School on the EDVAC sat in on the Moore School meetings at which the stored program concept was elaborated.

Von Neumann wrote up an incomplete set of notes ( First Draft of a Report on the EDVAC ) which were intended to be used as an internal memorandum describing, elaborating, and couching in formal logical language the ideas developed in the meetings.

ENIAC administrator and security officer Herman Goldstine distributed copies of this First Draft to a number of government and educational institutions, spurring widespread interest in the construction of a new generation of electronic computing machines, including EDSAC at Cambridge England and SEAC at the U. S. Bureau of Standards.