The difference between the Gates-Allen software library and the software library in the drawer by the PDP-6 or the Homebrew Club library was that the former was for sale only. Neither Bill Gates nor Ed Roberts believed that software was any kind of sanctified material, meant to be passed around as if it were too holy to pay for. It represented work, just as hardware did, and Altair BASIC was listed in the MITS catalog like anything else it sold.
