A Discussion on Deprecated Tags in HTML

A Discussion on Deprecated Elements in XHTML

Older XHTML tags that have been superseded by other more functional or flexible alternatives are declared as deprecated elements by the World Wide Web Consortium (What’s a deprecated tag/attribute?). The reason for declaring many presentational elements deprecated is a desire for a clear separation between document structure and the presentation of the document (Avoid deprecated features of W3C technologies). Many presentational elements and attributes are being deprecated in favor of style sheets, which allow authors to suggest a presentation with more flexibility, without the sacrifice of accessibility (HTML 4 Deprecated Features). Web browsers may temporarily support deprecated tags, but eventually these elements are likely to become obsolete and will not be supported in the future. Because of this web developers should get in the habit of not employing these tags when developing web pages and to use the elements and style sheets that have been set up to replace them. The following text will give examples of 10 XHTML tags that have been declared deprecated, a description of the function of these tags, and the elements that have been created to replace them.

The directory list element (dir) has been deprecated in favor of the unordered list (ul) element.

The applet element, which defines an embedded applet on a web page, has been deprecated in favor of the object tag.

The font element, which defines the font face, size and color, has been deprecated in favor of font style sheets.

The basefont element has also been deprecated in favor of font style sheets.

The strike element (s or strike), which defines strike through text, has been deprecated in favor of text style sheets.

The center element, which is used to center text horizontally, has been deprecated in favor of the division (div) tag and style attribute.

The underline element (u), which defines underlined text, has been deprecated in favor of text style sheets.

The isindex element, which defines a single-line text input on a web page, has been deprecated in favor of the input tag.

The menu element, which defines a menu list, has been deprecated in favor of the unordered list (ul) and ordered list (ol) tags.

The blackface element, which is a WebTV element that displays text as double-weight bold, has been deprecated in favor of style sheets.

Deprecated features are sure to become obsolete in future versions of XHTML. There is already a version of XHTML, XHTML 1.0 Strict, that does not employ the use of deprecated elements and attributes (XHTML 1.0 Deprecated Features). It is important for a web developer to know which tags have been declared deprecated so as not to develop web pages that, if so employing such tags, may create web pages that will not display when accessed by web browsers that do not support the use of the tags. If possible, a developer might want to replace any deprecated tags in existing web pages that they provide support for. Web developers should get in the practice of using the replacement elements and features instead of deprecated tags to ensure the functionality, accessibility and presentation of the web pages they create.


References

What’s a deprecated tag/attribute?
Retrieved August 13, 2007 from
http://www.codehelp.co.uk/html/deprecated.html

Avoid deprecated features of W3C technologies
Retrieved August 16, 2007 from
http://www.gawds.org/show.php?contentid=241

HTML 4 Deprecated Features
Retrieved August 13, 2007 from
http://htmlhelp.com/reference/html40/deprecated.html

HTML 4.01 / XHTML 1.0 Reference
Retrieved August 13, 2007 from
http://www.w3schools.com/tags

XHTML 1.0 Deprecated Features
Retrieved August 13, 2007 from
http://www.cs.sfu.ca/CC/165/sbrown1/wdgxhtml10/deprecated.html

An Overview of Empty Elements in HTML

An Overview of Empty Elements in HTML

In HTML the term “empty element” refers to elements defined by self-closing tags which are tags that do not require a closing tag. “This is generally because rather than defining an area of the page as one structural element or another, these tags define objects that should be displayed at that point on the page.” (Virtual Workshop – A Brief Guide to HTML). Some types of self-closing tags, such as ones that define imaging or line break elements, are used frequently in HTML so it is important to know the types, proper use and structure of these tags when creating web pages. The following text will give some examples of self-closing tags and how HTML employs these tags in the structure of a web page.

The self-closing tag hr is a horizontal rule element for positioning and formatting a horizontal line on a web page (hr – Horizontal Rule). The hr element uses the align, noshade, size and width attributes to specify the physical properties of the line on the web page.

The tag br is a line break element that is used to force a break in a line of text. The CLEAR attribute can be used with the br element to move text to the top left of a floating object such as an image (br – Line Break). In the following example:

The second paragraph would be placed below the floating image.

The tag img is an element that embeds an image in the current document at the location of the element’s definition (Objects, Images, and Applets in HTML documents). The img element has numerous attributes that can be used with it but a common one is the src (source) attribute which contains the directory path of the image file, in the event that the image file is not in the same directory as the web page document. An example of a image element with a source attribute would be:

The frame tag enables the display of more than one HTML document in the same browser window (HTML Frames). It is used within the frameset tag and specifies the name of the document to be displayed in the web browser. In this example the HTML document ABC will be displayed in the first column designated by the frameset tag and the document DEF in the second column:

The meta tag is inserted within the head tag of a web document to provide information about the page to a web browser (SearchEngineWatch: How To Use HTML Meta Tags). The description of a web page can be placed within a meta tag and a search engine would then display that description on the web browser. For example,

would enable the text declared in the content attribute to display if the web page was to be listed in the results of a search.

The link tag may only appear within the head tag of a web document to define the relationship between two linked documents (HTML Link Tag). There are numerous attributes that can be used with the link tag; some of the more common are the href attribute, which identifies the target URL of a resource, and the rel attribute which defines the relationship between the current document and the targeted resource. The following example defines a link to an external style sheet:

When using self-closing tags within HTML no mechanism to close the tag is required. However this is not the case when employing self-closing tags in other types of web page development languages. For example, in XHTML a mechanism to close a tag defining an empty element is required (tutorial). Therefore it is good practice to always place a space, then a forward slash ( / ) at the end of a self-closing tag, immediately before the closing angular bracket ( > ). Also, always remember to enclose all values of element attributes in quotes. An understanding of the protocols for the use of self-closing tags when defining empty elements is essential when working with HTML. Familiarity with the employment of these tags within the structure of a web page will significantly contribute to the functionality and appearance of the page.


References

Virtual Workshop – A Brief Guide to HTML
Retrieved August 01, 2007 from http://www.keithjbrown.co.uk/vworks/design/design_4.php

HR – Horizontal Rule
Retrieved August 01, 2007 from
http://www.htmlhelp.org/reference/html40/block/hr.html

BR – Line Break
Retrieved August 01, 2007 from
http://www.htmlhelp.org/reference/html40/special/br.html

tutorial
Retrieved August 02, 2007 from
http://www.easytutorials.eu/tutorial.html

Objects, Images, and Applets in HTML documents
Retrieved August 02, 2007 from
http://www.w3.org/TR/html4/struct/objects.html#h-13.2

HTML Frames
Retrieved August 01, 2007 from
http://www.w3schools.com/html/html_frames.asp

SearchEngineWatch: How To Use HTML Meta Tags
Retrieved August 01, 2007 from
http://searchenginewatch.com/showPage.html?page=2167931

HTML Link Tag
Retrieved August 03, 2007 from http://www.w3schools.com/tags/tag_link.asp

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