With help from the Computer History Museum in California, Microsoft has opened source code for MS DOS and Word for Windows to the public – two of the most widely used software from the 1980’s.
MS DOS, the “Disk Operating System” is from 1982 for IBM compatible personal computers. This version of the OS is only 12K bytes – only a fraction of the average storage space required for today’s operating systems (Windows 7 requires an average of 10GB). (Microsoft MS-DOS early source code from the Computer History Museum)
The version of Word for Windows made available is from 1990. (Microsoft Word for Windows Version 1.1a Source Code at Computer History Museum)
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