"Gay men are generally considered to be men who have sexual desires for other men, although this is an oversimplification of a complex issue. Although men have had sexual relationships with other men throughout recorded history, “gay” is a socioculturally constructed identity that is only about one hundred years old. Even in the early 21st century, not all men who desire other men, or have sex with them, consider themselves to be gay. In addition there is great diversity among those men who do adopt gay identities. Nevertheless gay men do have many commonalities, including a collective history and elements of a shared culture. Because gay men’s identities, experiences, and developmental trajectories continue to change, it is important to use the most current information about them."