Sorry for what may seem like a dummy question but- what is bus?  What are bus assignments?
 
Is it a form of subgrouping?  For example, would you send drums, bass, and rhythm guitar into one bus so you could control the entire rhythm section in one feel swoop, and then send that bus out to the master?  If that isn't it then what is it?
 
Thanks!

So I did a quick google for a youtube video, try this:
http://youtu.be/7LS4SZI0TOs
 
You might want to check out tutorials on Groove3 or other online documentation as well...
http://forum.cakewalk.com/New-To-X3-Is-the-SONAR-X2-Power-Guidebook-a-good-starting-place-m2958873.aspx
 

Len Rabinowitz
Sorry for what may seem like a dummy question but- what is bus?  What are bus assignments?
 
Is it a form of subgrouping?  For example, would you send drums, bass, and rhythm guitar into one bus so you could control the entire rhythm section in one feel swoop, and then send that bus out to the master?  If that isn't it then what is it?
 
Thanks!

"subgroup" would not be an inaccurate way to describe a bus.  The only reason I hesitate to give a strong yes is because  some software uses the term "subgroup" in a different way.  In simple terms a bus is a mixing path.  It can be used in the way you describe or broken down even further.  One could route all the individual parts of drum kit into a bus. You could go beyond that and route layered kicks into a kick bus and then route that bus into a drums bus.  A bus can also be used to house effects.  Instead of applying reverb directly to each track.  One can apply a reverb to a bus and have various tracks send to that bus. Probably easier to show in action:
 
http://www.youtube.com/watch?v=S7XErke7g4s

Ooops. just realized Alex posted a vid
 

I wonder why it's called "bus" (nothing to do with the vehicle, I hope). And I wonder why some posters mistakenly spell it "buss."

dubdisciple
Ooops. just realized Alex posted a vid

 
Typical, you wait for hours for nothing, then all of a sudden 3 buses turn up all at once 

I like it. 

Jlien X
I wonder why it's called "bus" (nothing to do with the vehicle, I hope). And I wonder why some posters mistakenly spell it "buss."

because it pops up now and then in manuals, books, etc.  I used to wonder if it was a British thing.  I have seen it pop up on educational sites and documents like here:
 
http://artsites.ucsc.edu/...ent/mixers/mixers.html
 
Even on commercial sites:
 
http://www.bhphotovideo.c...6_36_Input_4_Buss.html

Origin of the term "bus".  It appears to be a shortened version of the term omnibus and evolved from there : http://www.worldwidewords.org/articles/omnibus.htm

Being from the UK we say BUS.
I think it's just people typo'ing when they say BUSS.
 
Something is going on a bit like the pronunciation of the word "Linux":
http://www.youtube.com/watch?v=5IfHm6R5le0