Here's an O'ReillyNet article that attempts to define
in terms the average pointy-haired boss can understand.
"The most important difference between software created by the open
source communities and commercial software sold by vendors is that open
source software is published under licenses that ensure that the source
code is available to everyone to inspect, change, download, and explore as
they wish. This is the essential meaning of open source: the source
code--the language in which the software is written and the key to
understanding how the software works--can be obtained and improved by
anyone with the right skills.
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