Not many remember it, because the technology industry tends to focus on its future at the expense of its past, but in the beginning software was free. In both senses of the word free; it was available at no cost, and the source typically came without restrictions. One of the earliest user groups SHARE, founded in 1955, maintained a library, in fact, of users’ patches, fixes and additions to the source code of the IBM mainframe like a proto-GitHub. The modifications SHARE maintained were extensive enough, in fact, that in 1959 SHARE released its own operating system – what we would today refer to as a distribution, the SHARE Operating System (SOS) – for IBM 709 hardware.
IBM made available the software at no cost and in source code form because for the company at that time, the software was not the product, the hardware was. It wasn’t until June 1969 that IBM announced, possibly in response to an anti-trust suit filed by the United State Justice Department in January of that year, that it would “unbundle” its software and hardware.
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