Cost. In the 1990s, enterprise resource planning (ERP) and customer relationship management (CRM) software typically required expensive servers running a proprietary flavor of Unix (or possibly IBM's equally proprietary OS/400). But Linux runs on less expensive, standard PC servers and isn't proprietary.
Employee skill sets. Big companies with large IT departments are more likely to have a core of IT veterans with the skills necessary to administer one of the traditional server operating systems -- Unix or Microsoft Windows Server. Midmarket firms, on the other hand, tend to rely more on outside consultants and value-added partners that have a market-driven incentive to embrace new technology such as Linux.
This was first published in April 2005