The purpose of this lesson is to introduce web standards and establish why they are important. Specific standards (HTML, CSS, XML, and XHTML) will be defined.
At the completion of this exercise:
In the early days of the Web, everyone accessed the Web using a keyboard, mouse, and monitor. This is still the most common means of accessing the web, but there is a growing variety of technologies that are "web-enabled". People can access the web on handheld computers/PDAs, such as Palm Pilots and PocketPC devices. People can access the web on their cell phones, both visually (on a tiny screen) or audibly (using voice commands and synthesized speech output). People can access the web in their cars, again using an audible interface (no screen, no keyboard or mouse). People with disabilities also access the web and do so using a variety of technologies known as assistive technologies (more on this in the next lesson).
Even within the traditional combination of computer and monitor, there are a growing variety of browsers that people can choose from, including Microsoft Internet Explorer, Mozilla Firefox, Opera, Safari, and others. People use a variety of operating sytems, including Windows, Mac OS, and Linux. People have their computers set to a wide variety of screen resolutions, from 640 x 480 pixels to 1400 x 1050 pixels and beyond.
With all this diversity in the way people access the web, there's a very high probability that your website will look different to many of your visitors than it does to you. Despite these differences, the most important part of your website is its content, and all users should be able to access that. The only way to ensure that websites work across all devices and configurations is to develop in accordance with web standards. Web standards are the core set of rules for developing websites. It might be possible to develop sites that do not comply with standards, but doing so increases the likelihood that many people will be unable to access your site.
The central organization who is responsible for creating and maintaining web standards is the World Wide Web Consortium (W3C). Here are the definitions of the W3C standards that we'll be following in this course:
The following resources are the actual specifications for each of the standards listed above. These are technical documents, and can be challenging to read. However, they are the definitive source for each of these markup languages, and can be excellent resources. Look them over to see what constitues a standards document.
Great! Proceed to the next lesson.
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