Question

I'm not extremely linux familiar, but I've heard all these different types, like Ubuntu, Debian, Red hat, Fedora, etc. I assume some are sequential releases, but what's the difference between them?

Answer 1

1. Wikipedia: Comparison of Linux Distributions
2. Further reading at DistroWatch
3. Similar question: What are the differences between major Linux distributions? Will I notice?

Answer 2

"Linux" properly refers to the OS kernel.

By "different flavors of linux", you are referring to different Linux distributions. A "distribution" is a complete operating system -- a particular packaging of the kernel with various other utilities, services and shells that provide the rest of what users expect from an operating system. nik's answer provides some good links to start with.

The differences between distributions are in the particulars of

• what a distribution is designed to accomplish,
• which versions of what tools it includes to achieve that goal, and
• how it chooses to handle configuration and packaging.

A distribution aimed at desktop users typically includes the X-window system, a desktop environment, a printing subsystem, networking components, etc. One designed for servers often doesn't include X or a desktop environment, but adds services that aren't needed on a desktop (webserver, database, network filesystems, etc).