Have you ever wondered how the same program can work across so many different flavors of Unix?  One of the behind-the-scenes systems that makes this happen is GNU Autoconf, a program that makes it possible to write source code in a way that will work on many different computers.  Unix systems are largely, but not completely, source-code compatible, and Autoconf makes it possible for a programmer to identify these differences when the program is compiled, papering over them in the source code itself. 

Thinking about using open-source software in your business? That's a great idea, and might well save you money. But don't assume that the only cost will be installing and configuring the program. No, the biggest cost will be integrating your new program into your organization. The integration may well require a consultant, or an in-house expert in these matters. But even so, using open-source software almost guarantees that the integration will be easier and cheaper than would be the case with proprietary software.