This article presents a detailed timeline of events in the history of computing. For a narrative explaining the overall developments, see the related History of computing.
Stephen White: A Brief History of Computing, http://ox.compsoc.net/~swhite/history. An excellent Computer history site; the above is a modified version of his timeline, used with permission.
... three qualitatively different cases:
If the discriminant is zero, then there is a repeated solution x, and this solution is real. (Geometrically, this means tha ...