You just received an invitation to a dance, sweet sixteen, or maybe your cousin's wedding. Sweet! The invitation says "semi-formal attire." Wait, what does that mean? Generally, semi-formal and cocktail dresses have shorter hems (think mini dresses or high-low dresses, while black tie and formal events require gowns with floor-length hems. Of course, the style and fabric matters, too. More info here: Crack your formal dress code.
Photo courtesy of Unique Vintage