Below is shorten of my actual code. I try to keep the children div inside its parent div. It works in ie but goes lefty and not working in the others.
What causes this and how to solve.
			.width {
				width: 960px;
				margin: 0 auto;
				border: 1px solid #000;
			.left { float: left; }
			.right { float: right; }
			<div class="width">
				<div class="left">
					Lest Side
				<div class="right">
					Right Side
Thank you,