The float property in CSS is a blessing if you ask me. I use it almost exclusively for layout, with occasional tables or absolute/relative positioning. The float property leaves your layout incredibly fluid so that you can change it very easily. However, there are some difficulties that are easy to run into when using the float property.
What float essentially does is force block level elements to not actually take up space in the document. Only floating elements will move around other floating elements, but you might find that sometimes your elements overlap or float around another when you just don’t want it. This happens very commonly when you define the height of an object such as a div, and float elements inside of it which actually will exceed the height of that div. Some browsers will not expand the containing div automatically. Other times, you might have a div floating left, and another immediately after that, but you don’t want them next to each other horizontally. For all of these problems, there is one simple and easy solution:
The “clear: both” property: Think of the clear property as a horizontal line that forces everything written after it in markup to appear below it (within the containing div). The most common implementation I’ve ever seen is a div solely created to contain this property. I’ve seen this all over the web, and I use it all the time, without any hesitation. Make a CSS declaration like this:
div.clear{ clear: both; }
And the HTML:
<div class="clear"></div>
Putting this div below another other set of divs will essentially create a forced break between everything written above it in the HTML, and everything written below it. This is limited to the containing div though. I personally can only think of a single situation when you wouldn’t want it limited to the containing div (if you wanted to force a two column layout to be the same height, but you just can’t do that). So yeah, stick to this… you won’t regret it!