Small social group whose members share personal and enduring relationships. -People share many activities, spend a great deal of time together, and feel they know one another well. -Families are these types of groups in that they are the first groups we experience in life and because they are of central importance in socialization process.
Cocktail dress: Formal, usually knee-length, something more like an LBD Prom dress: VERY formal, usually floor-length, basically think ball gown, bedazzled. Evening gown: VERY formal, a lot like prom dress, less bedazzled That's what I think the difference is.
A semi-formal evening wedding is just slightly dressier than a semi-formal daytime wedding, but you can wear the same thing to both. A cocktail dress and heels or dressy separates (same as daytime) will look great but don't forget that an LBD is also an excellent option for a semi-formal evening ceremony.