Unless specifically noted otherwise, all models are assumed to be carrying a hand weapon of some kind. The term "hand weapon" is used to describe any weapon held in one hand and not otherwise covered by the rules. As such it includes sword, axes, clubs, maces etc.
Rules: No special weapon rules apply to hand weapons but they do have the advantage hat they can be used in combination with each other (see "Fighting with a weapon in each hand") or with shield (see "Fighting with a hand weapon and shield"). [p. 91 of RB]