Halfings have no quarrel with anyone and as such they are able to converse with people of all races and backgrounds with ease.

You gain advantage in persuasion rolls

The small size combined with nimbleness of a halfling allows halfling to simply slip pass their foes

You can move through the space of any creature that is of a size larger than yours.

When you roll a 1 on a D20, you can re-roll it. You must use the new roll.

Halflings have a strange resistance to any sorts of magic that attempt to influence their mind

You gain advantage on saving throws against frightened, charm, corruption or curse effects of any sorts(DM interpretation). 

Halflings are extremely small, allowing them to hide almost anywhere

You can attempt to hide anywhere near objects that are smaller than you 

Those around halflings tend to be in good mood and hard to become under a hostile influence

Allies within 15 feet of you can add 2 to a saving throw against being charmed or frightened.