One of the key ideas in the "first draft" was that the programmer could store a program in the computer's electronic memory, rather than program the computer using mechanical switches and patch cables. This and other ideas in the paper had been discussed in the EDVAC study group before von Neumann joined the group. The fact that Eckert and Mauchly, the actual inventors and designers of the ENIAC, were not named as co-authors created resentment that led to the group's dissolution at the end of the war.