XHTML | ||||||||||||||||||
| HTML Root, HEAD and BODY Tags | |
|---|---|
| <html xmlns="https://www.w3.org/1999/xhtml" xml:lang="en" The html element is the "root" element of the document, and the opening and closing html tags enclose all the data in the html document proper. The root element of the document must contain a declaration specifying the "XML namespace" (xmlns). Including the "XML language" declaration (xml:lang) is "strongly suggested." So is using the deprecated "lang" attribute, for "backward compatibility" with old browsers. lang="en"><head> <title> </title> </head> <body> </body> </html> | |
| <head> <title> </title> </head> | The head tags contain instructions for web browsers and "behind-the-scenes" internet applications, e.g., search-engine robots; head data is not displayed on the web page itself. Only the document title must be contained inside the head element, but other elements usually appear, including tags that define meta, link, style, andscript elements. EXAMPLE: <head> <title>Ed's Guide to XHTML</title> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1" /> <link rel="stylesheet" type="text/css" href="class.css" /> <script type="text/javascript" src=" class.js"> </script> </head> |
| <title> </title> | The title is the one required element that falls inside the head element. This title shows up in the browser's title bar, and is used by the browser if the page is bookmarked. |
| <meta /> | The meta element is used primarily to provide instructions to the browser or to describe the content of the web page for indexing. It appears only within the head of the html file, but may be repeated as many times as needed. Each meta tag will have at least two attributes: one to identify the function of the tag, and the other to provide the "content." Choose the first attribute(s) from among:
content="?" EXAMPLES: <meta http-equiv="Content-Type" NOTE: The first example defines the "character set" (basically, the alphabet and punctuation marks) that the browser should use, so this particular meta element should always be included.content="text/html; charset=ISO-8859-1" /> <meta name="keywords" content="html,xhtml,markup language" /> <meta scheme="day-month-year" name="revised" content="09-12-2001" /> |
| The self-closing link tag creates a connection with another document, especially with an external "style sheet" that specifies how defined elements should be displayed. It appears only in the head, but may be repeated as many times as needed. Among the possible attributes, those for "relationship," "type," and "hypertext reference" (which specifies the URL of the linked document) are the most used. EXAMPLE: <link rel="stylesheet" type="text/css" href="name.css" /> |
| <style type="text/css"> selector1 { property: value } selector2 { property: value ; property: value } </style> The style element is the place to create an "internal" style sheet, an important part of a prescribed system called Cascading Style Sheets (CSS). Unfortunately, there are compatibility problems with coding for this element among past, present, and future browsers, so the best solution is: DON'T USE THIS TAG! At least for the time being. Instead, use the link tag to an "external" style sheet, and apply "inline" stylistic features (using the style, class, and id attributes) directly to tags within the body of the document. | |
| <script type="?"> </script> | Putting scripts in XHTML that were originally formulated for the old HTML encoding is problematic. The problem is that JavaScript typically makes use of characters that exclusively signify tags in XML, namely: the less-than symbol (<), the ampersand (&), and the character string: ]]> The "tag" function can be overridden by encapsulating the script in a "CDATA" element:<![CDATA[ ... ]]> But, the CDATA tag confuses many current browsers, so the best solution is to put your JavaScripts in a separate document (created in Notepad and saved with the filename exension: .js), and then refer to it with a "system resource controller" attribute (src).EXAMPLE: <script type="text/javascript" (NOTE: The language="javascript" attribute should no longer be used, even though you will probably see it all over the web. Also, even though the script tags are "empty" as used here, you should still use the opening and closing tag pair rather than turning it into a self-closing tag.)src="class.js"> </script> </head> |
| <body></body> | Opening and closing body tags enclose all the content that actually appears on the web page The body may include graphical and audio-visual elements in addition to text. |
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