Sex is a broad term that generally refers to sexual activity, which includes a range of behaviors that involve physical intimacy intended to arouse sexual pleasure. The most commonly known form is sexual intercourse, typically defined as the penetration of a woman's vagina by a man's penis (vaginal sex), but sex can also include other types such as oral sex, anal sex, manual stimulation, and even activities like kissing, caressing, and erotic communication. It can be experienced alone (masturbation) or with others and can serve multiple purposes, including pleasure, reproduction, emotional bonding, and intimacy. Importantly, all sexual activities should be consensual and comfortable for everyone involved. Sex also has biological and social dimensions. Biologically, "sex" refers to physical and physiological characteristics like chromosomes, hormone levels, and reproductive anatomy. Socially and personally, sex can include diverse expressions of sexuality and intimacy, influenced by cultural, relational, and individual preferences. In essence, sex is not just one act but a spectrum of behaviors tied to human sexuality, reproduction, and emotional connection.