Research: Demographics and Psychographics

Demographics are based upon quantitative data which provide the age, gender, nationality, occupation, ethnicity etc of the chosen audience. 
For example; demograpics (Income): if a person can command a high income, most likely he would purchase a luxury watches or cars.
For example; demograpics (Age): age is also a good way of determinant  such as teens(12-19), there are tech savvy, wants the latest fashion, technological innovated, most likely they will purchase Ipod and high-end mobile phones.

Whereas psychographics use qualitative data that reflects the attitudes, lifestyles and preferences of the audience. 
For example; psychographic (Social Class) : lower class, working class, middle class & upper class, always related to income.

Lifestyle : achievers, strivers & survivors
Personality : Compulsive, gregarious, authoritarian, ambitious.