The World Wide Web is a wonderful thing: computers all over the world –
connected together – sharing documents and multimedia. In recent years, the
World Wide Web has begun to grow beyond this comfy computer-based family of
devices. The Web is now accessible on mobile phones, handheld digital
assistants, and televisions.
This phenomenon has placed a considerable burden on content
authors. No longer can they write their documents with expectations on how that
content will be displayed. Each of these new devices represents a quite
different medium from the computer: the physical characteristics of the devices
are different, the relationship between the device and the user is different,
and the cost of using the device is different.
Until recently, authors had little choice but to author or
re-author their content with each device in mind. With the advent of Cascading
Style Sheets (CSS) and something called 'media types', this began to change.
In this chapter, we will learn how to use CSS and media
types to tailor our documents to different devices.
In this chapter we will cover the following:
What media types are and why we need
What the role of Cascading Style
Sheets is in supporting media types
How to associate style sheets with
different media types
How to use @media rules and @import
The differences between media types
and strategies for handling them
The future of style sheets in XML
First, we will define media types and try to understand why
they are important.