Lightning Bolt damages both Health and Magicka when cast, making the spell effective against other mages.
Lightning Bolt is a great spell to use against non-hostile or airborne Dragons, since the spell does not arc like an arrow, and it reaches its target instantly, unlike Firebolt or Ice Spike. However, Lightning Bolt does have a definitive range, and sometimes the dragon needs to be close enough to hit with the spell.
If the Dragonborn uses the spell just before a dragon shouts, the dragon will be prevented from doing so.
Only true when dual-cast in conjunction with the Impact perk. Charge and maintain the dual-cast until the dragon breathes in or rears its head back in preparation for a dragon breath, then release the spell to stagger the dragon.
Lightning Bolt will strike a target immediately when cast, unlike Ice Spike or Firebolt, which makes it useful for firing at enemies from long-range.