Editing Two's complement (section)

==History==
The [[method of complements]] had long been used to perform subtraction in decimal [[adding machine]]s and [[mechanical calculator]]s. [[John von Neumann]] suggested use of two's complement binary representation in his 1945 ''[[First Draft of a Report on the EDVAC]]'' proposal for an electronic stored-program digital computer.<ref name = "von Neumann 1945">{{Citation | last = von Neumann | first = John | author-link = John von Neumann | title = First Draft of a Report on the EDVAC | year = 1945 | url = http://web.mit.edu/STS.035/www/PDFs/edvac.pdf | access-date = February 20, 2021 }}</ref> The 1949 [[EDSAC]], which was inspired by the ''First Draft'', used two's complement representation of negative binary integers.

Many early computers, including the [[CDC 6600]], the [[LINC]], the [[PDP-1]], and the UNIVAC 1107, use [[ones' complement]] notation; the descendants of the UNIVAC 1107, the [[UNIVAC 1100/2200 series]], continued to do so. The [[IBM 700/7000 series]] scientific machines use sign/magnitude notation, except for the index registers which are two's complement. Early commercial computers storing negative values in two's complement form include the [[English Electric DEUCE]] (1955) and the [[Digital Equipment Corporation]] [[PDP-5]] (1963) and [[PDP-6]] (1964). The [[IBM System/360|System/360]], introduced in 1964 by [[IBM]], then the dominant player in the computer industry, made two's complement the most widely used binary representation in the computer industry. The first minicomputer, the [[PDP-8]] introduced in 1965, uses two's complement arithmetic, as do the 1969 [[Data General Nova]], the 1970 [[PDP-11]], and almost all subsequent minicomputers and microcomputers.