Yeah, sword terminology can get confusing. Part of the reason for that, is simply that back in the day, they just called it a "sword", and didn't get hung up on classifications.
For the most part, if someone is referring to "arming" or "broad" swords, they probably mean one-handed.
If they say "bastard sword" or "hand and a half", they're probably referring to a longsword (which is mostly two-handed, but can be used with one).
If they say "great sword", they're probably referring to the larger two-handed swords. These have more period correct terms for them, but those terms still just mean "two handed" or "large sword", such as Zweihander (German), Spadone (Italian), Montante (Iberian).