Question

what is sex

Answer 1

Sex, often a shorthand for sexual intercourse.
Sexual intercourse (aka coitus/copulation) is sexual activity typically involving the insertion and thrusting of the p***s into the va***a for sexual pleasure, reproduction, or both. This is also known as vaginal intercourse or vaginal sex.

We divide sex into two categories 1)penetrative sex, 2)non-penetrative sex.

penetrative sexual intercourse include
anal sex (penetration of the a**s by the p***s),
oral sex (penetration of the mouth by the p***s or oral penetration of the female genitalia),
fingering (sexual penetration by the fingers), and penetration by use of a d***o (especially a strap-on d***o)

while non-penetrative sex has been labeled "outercourse",generally excludes the penetrative aspects of va***al, a**l, or oral sexual activity, but includes various forms of sexual and non-sexual activity, such as frottage, mutual masturbation, kissing, or cuddling.

Reproductive sexual intercourse between non-human animals is more often called copulation, and sperm may be introduced into the female's reproductive tract in non-vaginal ways among the animals, such as by cloacal copulation