CSS Clear

What is it?

[webfoo]

Would someone explain to me what is CSS Clear? I've heard of it and even seen it but still lack a fundamental understanding of it.

[SuzyUK]

hmm

do you want this:
9.5.2 Controlling flow next to floats: the 'clear' property [w3.org]
or
do you want some or all of that in English?

i.e. do you already use floats or know it's related to floats?