Defenses: Halflings gain a +4 on saving throws against magic
Attack Bonuses: Halflings have a +1 bonus when using missile weapons.
Classes: Halfling Characters may advance as Fighters, but they are limited to 4th level simply due to their diminutive size and generally non-aggressive nature. They may also choose to be Thieves, in which case they have no limit on level advancement. Halfling characters may take advantage of any XP bonus due to high Attribute scores to gain experience more quickly. Halflings who are not player-characters might have classes, abilities and limitations which are completely different from those of a Halfling adventurer.
The nature of the Halfling race as a whole is determined by the Referee, and might include non-player characters of any class.