What version of Unix?

[thechyld@pcc-uky.campus.mci.net (DarkChyld [Ronald J. Hall])]

  Hi. What version of Unix are we closest to? I'm asking because I've just
  picked up a Unix reference book, and it lists several different flavors.
  (SunOS, Solaris, BSD, FreeBSD, Linux, etc, etc,...) Minix is mentioned in
  there, as well. If I know what release we are closest to, then I can 
  figure out what commands will most likely work.
  
  (this ref. book has already been a time-saver, I found out the up-arrow
   key will scroll through your previously typed commands!)
   
  Thanks! (and Mint rules!) ;-)
  

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