From DDO wiki
Arcane spells are subject to Arcane Spell Failure (ASF), a chance for the casting to fail if the caster is wearing armor or a shield.
- Sorcerers, Wizards, and Bards are the primary users of Arcane spells.
- Rangers and Druids have access to a mix of both Arcane and Divine spells while Artificers have a mix of Infusion spells and Arcane spells, but none of the three are subject to Arcane Spell Failure when casting Arcane spells.
- A select few spells are both Arcane and Divine.