Women:  Wear a shorter dress with some frill. The classic little black dress makes for great cocktail attire, and is the easiest to show your personality by accessorizing to suit your mood. 

Men: Wear a dark suit, coat, and tie. Opt for dark jeans paired with a jacket and tie is also acceptable at some cocktail events, depending on how casual the atmosphere or event.

When to wear it: Adult Birthday Parties, Soirée, and Evening Social Events.