There are three basic concepts in responsive web design, creating flexible layouts, creating flexible content, and using media queries to handle problems caused by major differences in screen size. Though flexible content is arguably much more important, flexible layouts with media queries are the poster child of responsive web design, and this is the subject of this chapter. Without a flexible layout, it’s difficult if not impossible to have flexible content. So this is a good starting point for digging into responsive web design. In the next chapter we will focus specifically on creating flexible navigation, something closely related to flexible layouts. We discussed both briefly in Chapter 1, but here we will discuss these topics in depth and give several more examples. In Chapter 5 we will discuss flexible content in depth.