The number of people you are having sex with (women are not supposed to have sex w multiple partners) Sexual double standard served as the premise for dating rituals. Back then had to flirt like a virgin. Girls had to dress shy, not sexually explicit at all, etc. Girls expected not to initiate anything explicit, like sex. Hooking up can refer to relatively insignificant intimate interactions. In the past, kissing would be characterized as making out. Simple making out, touching, different meanings for diff people. Has caused a change in the sexual behavior of college students. Has caused general liberalization of attitudes towards sexuality. Has caused an increase in sexual partners. Meaning of hooking up varies by class, religious beliefs ethnicity. Teen perceptions of parental beliefs and relationship with parents. Differing views on what is sexual activity. Rational choice related to economic and cultural context.