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New AUS Standard - Validation

From: Robert Savellis <savellis@ozemail.com.au>
Date: Fri, 29 Aug 1997 16:10:08 +1000
Message-Id: <1.5.4.32.19970829061008.007220b8@ozemail.com.au>
To: w3c-wai-ig@w3.org




Could you please review the following proposed AUS Standard of Validation
and supply 
me with your feedback?

This can also be found on http://www.agd.nsw.gov.au/draft.html



VALIDATION

   1.Webpages must be validated against the official HTML specification
before being put online. 

Validation is simply the process of highlighting HTML errors in a webpage.
Web browsers themselves are very poor at this task as they are deliberately
designed to be very "forgiving" of many errors. However, not all browsers
are "forgiving" of the same errors. As such, what might look great in one
web browser, could look disastrous (and/or innaccessible) in another.
Therefore, the goal of validation is to ensure that only one specification
of HTML is used when designing webpages, inorder for webpages to be viewed
consistently and as intended, by all web browsers (referred to as
Interoperability). 

The most common method of validation today is by way of software programs or
robots called validators. These validators look at the underlying code of a
webpage, and identify errors by checking against a HTML specification. This
specification (called a "Document Type Definition" or "DTD"), is an baseline
standard that web browsers support. 

          NOTE: The term "errors" covers HTML syntactical errors,
Unrecognised proprietary tags,
          and Kludging (the use of the wrong tags to attain a desired effect).

How To Validate a Webpage 
Validation is a very simple process. The validator highlights errors (if
any) on the selected page. Then the error must be corrected manually, before
running the validator again to ensure that the error has been removed. In
most cases, the most difficult part of validation is to work out why (what
seems like) perfectly correct code keeps getting an error. 


Online Validation 
   1.Go to the validator that has been selected 
   2.Once there, select the proper DTD to check against (W3C 3.2) 
   3.Type in the URL of the page you want to validate 
   4.Select whether to check one page or multiple pages at a time (if option
available) 
   5.Print out the results 
   6.Go into your HTML editor and correct the errors 
   7.Go back to the validation service and check your corrections 



Desktop Validation 
   1.Install the validator onto your computer. 
   2.Select the proper DTD to check against (W3C 3.2) 
   3.Type in the URL of the page you want to validate 
   4.Select whether to check one page or multiple pages at a time (if option
available) 
   5.Edit the results 
   6.Re-validate your corrections 
   7.Edit your results again if errors persist 



Validators 

     *Spyglass This validation program is free, downloadable and very easy
to use. 
     *Web Techs HTML Validation Service This online validation service can
validate one page or multiple pages      at a time. It
     provides the option of checking against a number of DTDs, and displays
the line number of the error with a      short explanation. 
     *A Kinder, Gentler HTML Validator This online validator highlights
every error with an arrow, and provides      an explanation of the error. 


The Official Specification
W3C HTML 3.2 is the current DTD, and webpages should be checked against this
specification. Most validators will however allow for a webpage to be tested
against a number of DTD's, including the Netscape DTD, the Microsoft
Internet Explorer DTD, and previous DTD's. (The Netscape and Microsoft DTD's
are explained in the section entitled "extensions"). 

          Warning: Validation of a webpage against the official HTML
specification does not necessarily
          make that webpage accessible. Accessibility primarily relies on a
series of design decisions.


The Formal Public Identifier
Many webpages that have been successfully validated indicate this by
presenting a Formal Public Identifier (FPI) on the very first line of the
code of every page. An FPI identifies which version of the HTML DTD the
webpage conforms to. An FPI is not required, however it does provide web
browsers and people reading your source code an indication as to which
specification the webpage conforms to. Following are examples of FPI's: 

     "-//W3C//DTD HTML 3.2//EN" 
     "-//W3C//DTD HTML 4.0 Draft//EN" 
     "-//IETF//DTD HTML 2.0//EN"> 
     "-//Microsoft//DTD Internet Explorer 2.0 HTML//EN" 

Extensions
Netscape and Microsoft have developed, and continue to develop, proprietary
tags (HTML extensions) that are not part of the official DTD specification
of HTML. Because these web browsers control the vast majority of the browser
market, some people wrongly believe that these extensions are infact part of
the official HTML specification. 

The issue of whether to use extensions or not is a very contentious one. By
using extensions offcourse, the goal of an official DTD is thwarted. AUS
Standards recommends that all extensions should be avoided in web design. It
is however recognised that the use of extensions can be sometimes justified if: 

   1.The decision was based on a desired (but not universal) effect 
   2.The resulting inconsistency in design will not adversly effect viewers 
   3.The browsers that do not recognise this extension do not crash or react
adversly 
   4.The browsers that do not recognise this extension are not excluded from
the content 

If extensions must be used, it is recommended that they get viewed from a
number of different web browsers to check on how they display. For those who
do not have access to a wide variety of web browsers for testing purposes,
an online webpage tester called Bobby http://www.cast.org/bobby/, can be
used. This will allow you to see how your pages would look via a variety of
different browsers, including Lynx. 

                                                                            
   Back To Index 

  

Regards

Robert Savellis
                                   


----------------------------------------------------------------------------
Robert Savellis: Web Project Manager       Email:  savellis@ozemail.com.au
-Attorney General's Department             Office: (02) 9228-8327 or 9228-7986
http://www.agd.nsw.gov.au                  Fax: (02) 9228-8080
                                           Mobile: 014-030-007
                      -AUS Standards-
          http://www.agd.nsw.gov.au/standards.html
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Received on Friday, 29 August 1997 02:09:10 GMT

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