See the wiki
http://en.m.wikipedia.org/wiki/Western_(genre)
Under themes
And characteristics
to clarify...
I think most people know a western has horses and is set in american west between 1820-1900.
The PBS historical reality show "Texas Ranch House" from 2006
http://www.pbs.org/wnet/ranchhouse/
felt like a western with some of the scenes.
I wouldn't mind seeing another one with a different group of people maybe all adults and no kids. Not on PBS but instead on cable.