Two's complement was described carefully in Preliminary design of the logical design of an electronic computing instrument¹ §5.7 (Burks, Goldstine, von Neumann,

Two's complement was described carefully in Preliminary design of the logical design of an electronic computing instrument¹ §5.7 (Burks, Goldstine, von Neumann, 1946), but it's not an easy read. I suspect some early machines used signed-magnitude or one's complement simply because they didn't get it. ¹ https://www.cs.princeton.edu/courses/archive/fall13/cos375/Burks.pdf https://www.cs.princeton.edu/courses/archive/fall13/cos375/B...