The black party dress, black cocktail dress, black evening dress or whatever you want to call it, they all derive from the same "little black dress" that was introduced by Gabrielle (Coco) Chanel in 1926. And it's a good thing she did because around that time women started to wear less conforming clothing including more comfortable dresses that were less lengthy. 
Coco's design was a jersey dress, sleeveless with a wider neck and reached down to just above the knee. It was the first time that this much of the neck, arms and legs of a woman had been exposed. Plus it was black, and until this moment black was only reserved for mourning and death, not everyday fashion. Today, the first born little black dress has fully grown to a timeless ladies wardrobe necessity, thank-you Coco Chanel!
I'm a guy and my opinion the black party dress is just simply one of the most attractive garments a woman can wear. There is just something about the dresses in the way they are so beautiful and at the same time almost highlighting the women that wear them. They can be fun and flirty or classy and enchanting, and a lot of the time they can be almost dangerous and downright seductive.
Finding a black party dress that is right for you simply depends on your own preference. What do you like about yourself? If it's your bust, check out dresses that are fitted at the top with plunging necklines. if you like your arms and shoulders then go for a strapless one, and if your a fan of your legs and butt, scope out a shorter dress that really hugs your hips. There are lots of choices but you can really cut them down if you have a particular look in mind before you shop.
Source : http://ezinearticles.com/?The-Black-Party-Dress---A-Ladies-Wardrobe-Necessity&id=3353207
