Rudin wrote:
You should try Debian or Slackware next. They are fairly easy to use, but a bit more intense than Ubuntu.
I second Debian. It's what Ubuntu is (mostly) built on & is widely used. It's already cross compiled for various platforms and generally speaking, has massive amounts of community support and documentation. Also, many embedded systems seem to use it that don't use a proprietary distro. You can get your feet wet on that end by playing with any of the ARM-compiles, including several for Raspberry Pi & similar boards.
Slackware is a one man show (-ish) & seems to have slowed down quite a bit. Last version was 14.1, released in November 2013. It has also stayed its own course, which may be viewed as being somewhat silo'ed.
If you really want to learn Linux, I cannot recommend highly enough Linux From Scratch. Just...make sure you have a spare system (an old, outdated laptop works fine) in addition to whatever you want to use every day. Basically, you start out with a kernel and libraries, just barely enough to prep a drive, install the kernel and basic libraries and make it boot. From there, the documentation (it's a book, really) walks you through building a full system customized & optimized for that system. IMO, there is no better way to learn Linux. I find myself walking through it every time there is a major kernel revision or init change.
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