Floating elements within a div, floats outside of div. Why?

Question

Say you have a div, give it a definite width and put elements in it, in my case an img and another div.

The idea

Answer 1

There's nothing missing. Float was designed for the case where you want an image (for example) to sit beside several paragraphs of text, so the text flows around the image. That wouldn't happen if the text "stretched" the container. Your first paragraph would end, and then your next paragraph would begin under the image (possibly several hundred pixels below).

And that's why you're getting the result you are.