Demographics refer to factors of a target market like age, gender, income, and residence. This data is likely to be tracked by government agencies for statistical purposes.
Psychographics look beyond someone's age, socioeconomic status, and other demographic attributes to who they are people; their likes and dislikes, behavior, and cultural dimensions. This information is usually either generated out of surveys, or by tracking individual's online behavior and purchases. It can be more difficult to access.