Electronic Books

For example, this image tag

has two attributes: the image source, which has the value "images/?¬? do.
gif" that de?¬? nes its relative location on the server, and an alternative text
description, which has the value "a picture of my dog" that appears
on-screen if the image fails to load, or that could be read aloud by a screen
reader. Both these attributes are part of the structure of the document.
Before Web standards, it was common practice to load up tags with additional
presentational attributes, such as text sizes and colors. Now, we can
move all presentational information into the style sheet and thereby greatly
reduce the complexity of our markup and use only attributes that de?¬? ne
document structure.
Providing a means of separating a document??™s structure from its
presentation was the core objective in the development of Web
standards, and it is key to development of content that is both portable
(can be displayed on multiple devices) and durable (ready for
the future).
The Top 10 Bene?¬? ts of Standards-Based Coding
You may be wondering ???Why should I bother to change the way I have been marking up pages for years???? Here are 10
great reasons to adopt standards-based coding practices:
1. Deliver to multiple user agents. The same piece of marked-up content is readily deliverable in a wide variety of
user agents, the collective name for devices that can read XHTML, such as browsers, handhelds like smartphones,
cell phones with browsers, and screen readers that read text for the sight impaired.


Pages:
4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28