Halflings

In many ways, figuring out what a base D&D Halfling means to me was more difficult than for Elves.  Whereas Elves have a multitude of interpretations and aspects, Halflings have almost none.  You have Hobbits, Kender, and Athasian Cannibals/or other "Extreme" interpretations. 3e did away with the three distinct subgroups (tallfellow, stout, hairfoots) which I think is a shame as it gave something special to them as a race choice.  It was an understandable choice since it was tied to a percentile roll.

Baseline Halflings:

• The origins of Halflings, Hobbits in their own language, has been lost along with many aspects of their history, culture, and language.
• Halflings can be found throughout the realms, typically in proximity to other groups.  Much like humans their appearance and traits vary depending on the region.
• Their lifespans and aging a similar to humans, but they tend to be more spry in their older years.
  
• There are a small number of Hobbit lands, usually in out of the way area.  In these places more traditional (if not original) Hobbit lifestyles are prevalent.  Their relative isolation has given rise to distinct family traits among the inhabitants. 
• In areas where other cultures have overtaken the lands, Halflings generally adapt to the local customs.
• While they don't tend to form their own neighborhoods or enclaves in these cases, they do group along extended family lines.
  
• The Hobbit mind tends to be averse to complexity.  They enjoy simple work, and comforts, working to get things "just so"
  
• The Hobbit language has generally been reduced to a few words and colloquialism mixed into the common tongue.  Even within Hobbit lands, it is reduced to academic or ceremonial use.  Many Halflings don't even know it anymore, instead speaking the languages of other nearby cultures.
  
• Re-discovery of their shared culture is often a driver for adventuring Hobbits.

So there you have it.  Turning the fact that there is so little exploration of Halflings, and that no one ever takes Halfling as a language into their Culture.