AKA: breasts, baps, bazookas, bazooms, boobies, bosoms, bristols, bust, busters, hooters, jubblies, jugs, knockers, melons, norks, orbs, titties, tits.
What are they for?
To produce milk when a woman has a baby. The reason men are attracted to them is probably because they’re a sign of fertility (being able to have a baby).
When do girls start growing boobs?
Some girls start developing breasts aged eight or nine, but others don’t start until their late teens or even early 20s.
When do I know mine have started growing?
Your nipples will probably get larger and stand out more than they used to, and the circle of skin around your nipples (the areola) will get darker and larger.
As they’re growing, boobs can be tender and painful to touch.
Sometimes one breast will start developing before the other. But most women’s boobs look pretty much the same size when fully developed. (Although no woman’s breasts are exactly the same size.)
Can I do anything to change their size?
Not without major surgery. Most women worry about the size of their boobs at some point, whether they’re large or small. The best thing you can do for yourself is love your body just as it is.
When will I need a bra?
As soon as you can feel your boobs wobbling when you walk. You don't ever have to wear one, but it's usually more comfortable. If you never wear a bra your boobs might start sagging.
For your boobs to be properly supported your bra needs to be the right size. Most department stores, underwear shops and some big shops like Marks and Spencer offer a free measuring service.
Further help and advice
• What happens at a bra fitting?
• puberty101.com
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Pictures posed by models.