New types of relationships formed; it was possible for people to live together without marrying and without children.
Information about human sexuality grew, and with it an acceptance of all types of sexual orientations is becoming more common.
As humans societies have evolved from hunter-gatherers into civilized societies, there have been substantial changes in relations between men and women, with perhaps one of a few remaining biological constants being that both adult women and men must have sexual intercourse for human procreation to happen.
Humans have been compared to other species in terms of sexual behavior.
Communities exerted pressure on people to form pair-bonds in places such as Europe; in China, society "demanded people get married before having a sexual relationship" and many societies found that some formally recognized bond between a man and a woman was the best way of rearing and educating children as well as helping to avoid conflicts and misunderstandings regarding competition for mates.
Generally, during much of recorded history of humans in civilization, and into the Middle Ages in Europe, weddings were seen as business arrangements between families, while romance was something that happened outside of marriage discreetly, such as covert meetings.
These people will have dates on a regular basis, and they may or may not be having sexual relations.
Although in many countries, movies, meals, and meeting in coffeehouses and other places is now popular, as are advice books suggesting various strategies for men and women, in other parts of the world, such as in South Asia and many parts of the Middle East, being alone in public as a couple with another person is not only frowned upon but can even lead to either person being socially ostracized.
Behavior patterns are generally unwritten and constantly changing.
There are considerable differences between social and personal values.
However, one particularity of the human species is that pair bonds are often formed without necessarily having the intention of reproduction.
In modern times, emphasis on the institution of marriage, generally described as a male-female bond, has obscured pair bonds formed by same-sex and transsexual couples, and that many heterosexual couples also bond for life without offspring, or that often pairs that do have offspring separate.