Editing HTML editor (section)

==Valid HTML markup==
HTML is a structured [[markup language]]. There are certain rules on how HTML must be written if it is to conform to [[W3C]] standards for the World Wide Web. Following these rules means that web sites are accessible on all types and makes of computer, to able-bodied and people with disabilities, and also on [[wireless]] devices like mobile phones and PDAs, with their limited bandwidths and screen sizes. However, most HTML documents on the web do not meet the requirements of W3C standards. In a study conducted in 2011 on the 350 most popular web sites (selected by the Alexa index), 94 percent of websites fail the web standards markup and style sheet validation tests, or apply character encoding improperly. Even those syntactically correct documents may be inefficient due to an unnecessary use of repetition, or based upon rules that have been [[Deprecation|deprecated]] for some years.
Current W3C recommendations on the use of CSS with HTML were first formalised by W3C in 1996<ref>{{cite web|url=http://www.w3.org/TR/CSS1 |title=Cascading Style Sheets, level 1 |publisher=W3C |access-date=2013-10-23 |author1=             Håkon Wium Lie |author2=Bert Bos }}</ref> and have been revised and refined since then.<ref>{{Cite web |title=Cascading Style Sheets Level 2 Revision 1 (CSS 2.1) Specification |url=http://www.w3.org/TR/CSS21/ |website=W3C}}</ref><ref>{{Cite web |title=XHTML™ 1.1 - Module-based XHTML - Second Edition |url=http://www.w3.org/TR/xhtml11/ |website=W3C}}</ref>

These guidelines emphasise the separation of content (HTML or XHTML) from style (CSS). This has the benefit of delivering the style information once for a whole site, not repeated in each page, let alone in each HTML element.  WYSIWYG editor designers have been struggling ever since with how best to present these concepts to their users without confusing them by exposing the underlying reality.  Modern WYSIWYG editors all succeed in this to some extent, but none of them has succeeded entirely.

However a web page was created or edited, WYSIWYG or by hand, in order to be successful among the greatest possible number of readers and viewers, as well as to maintain the 'worldwide' value of the Web itself, first and foremost it should consist of valid markup and code.<ref name="RefactoringHtml">{{cite book
|title=Refactoring HTML
|last=Harold
|first=Elliotte Rusty
|year=2008
|publisher=Addison Wesley
|location=Boston
|isbn=978-0-321-50363-3
}}</ref> It should not be considered ready for the World Wide Web, until its HTML and CSS syntax have been successfully [[Validator|validated]] using either the free W3C validator services ([http://validator.w3.org/ W3C HTML Validator] and [http://jigsaw.w3.org/css-validator/ W3C CSS Validator]) or some other trustworthy alternatives.<ref name="RefactoringHtml"/>

[[Accessibility]] of web pages by those with physical, eyesight or other disabilities is not only a good idea considering the ubiquity and importance of the web in modern society, but is also mandated by law. In the U.S., the [[Americans with Disabilities Act]] and in the UK, the [[Disability Discrimination Act]] place requirement on web sites operated by publicly funded organizations.  In many other countries similar laws either already exist or soon will.<ref name="RefactoringHtml"/> [[Web Content Accessibility Guidelines|Making pages accessible]] is more complex than just making them valid; that is a prerequisite but there are many other factors to be considered.<ref>{{cite web|url=http://www.w3.org/TR/WCAG20/|title=Web Content Accessibility Guidelines (WCAG) 2.0|publisher=W3C|year=2008|access-date=2013-10-23}}</ref> Good web design, whether done using a WYSIWYG tool or not needs to take account of these too.

Whatever software tools are used to design, create and maintain web pages, the quality of the underlying HTML is dependent on the skill of the person who works on the page. Some knowledge of HTML, CSS and other scripting languages as well as a familiarity with the current W3C recommendations in these areas will help any designer produce better web pages, with a WYSIWYG [https://jsfeed.io/ HTML editor] and without.<ref>{{cite web|url=http://www.w3.org/MarkUp/Guide/ |title=Dave Raggett's Introduction to HTML |publisher=W3C |date=2005-05-24 |access-date=2013-10-23}}</ref>