what is the purpose of having sex?

From a physical standpoint, to release tension, and and provide feelings of ease and relaxation. From a relationship point of view, to provide opportunities for communion between you and your partner. One of the many side effects of heterosexual sex, is the creation of children.

Peace!

It's a primal urge. It feels good. Some people view it as an emotional connection, some view it as stress relief.

Some would argue that it's only for procreation but they can't answer:

1. Why every single time you have sex you don't get pregnant.

2. Why your sex drive doesn't go away if you're sterile.

3. Why it's pleasurable.

These three things defy a strictly procreation stance.

It's our nature, the way life exists and a way life enjoys itself, although humans and dolphins are the only animals who use it for pleasure. It's also much of the reason how we've understood how the world works.

Pleasure!

Fireball has it right. the closeness during sex is amazing. As well as after. Having sex with someone you love is a vastly different experience then having sex with someone you don't love.

And the procreation part.

We give it whatever purpose we want. Some do it for pleasure, some do it to bond, some do it to ease boredom, some do it in exchange for money, some do it to fit in with their peers. So many reasons.

Pleasure and procreation and with the over population of this planet, I'd like it to be purely for pleasure for a long time!

Ultimately = Procreation.

Generally = Pleasure.

It depends on the situation. I could be a couple trying to conceive a child or a couple expressing their feelings for each other or strangers making each other ***.

In order for a thing to have a "purpose", there has to be someone who designed that thing and had a reason in mind. Otherwise, it's "purpose" is what anyone uses it for and thinks about it. In terms of sex, for me it has quite a few purposes, only the least important of which is procreation.

Opinions vary of course.