Question by dan G: What are the differences between UNIX and Linux, and what about all those choices within Linux?
What are the operational differences between Linux and UNIX? Why would a programmer choose one over the other? What about software selection and ease of programming (with already basic knowledge of programming, and wanting to dive in to open source)?

In terms of Linux, what makes things like Red Hat cost money and things like Ubuntu not? Is pay-for OS based on Linux better quality than freely distributed OS? What is the best choice for Linux-or-Unix OS for a budding programmer?

Best answer:

Answer by Steven
Unix is old. Originally, there was no GUI on Unix. It was only command line, like DOS but more sophisticated.
Linux is a port of Unix onto various platforms, mostly “Wintel”, but Tivo and Sony, etc use it in their products.
When you pay money for it, you should get something that has been well tested and complete, however, an army of amateurs will always be more creative and innovative. As a budding programmer, a few bugs to solve is a good exercise. If you are not interested in the inner working of the OS, then you should stick with Microsoft.

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