Use a hyphen (-) for compound words (e.g. ‘two-dimensional’) as well as for a minus in mathematical description.
an en-dash (–) to link numbers, nouns or names (e.g. 220–240 Volts, electron–positron collisions, Einstein–Rosen–Podolsky paradox),
and an em-dash (—) to link sentences or clauses — this is what we would regard as a ‘normal’ dash.
だそう。ちなみにhyphen→ en-dash → em-dash の順に長くなる。em-dashは全角ダッシュ。