Boot Camp

HTML/XHTML Basics
Currently, the normal doctype for new and developing websters to start with is XHTML
1.0 Transitional, which helps browsers assume the web page has been designed using standards
mode. It is also more forgiving that XHTML 1.0 Strict and allows for the occasional
creep in of a gracefully depreciating tag. Designers then often move into XHTML 1.0 Strict,
but you may find it easiest to work into the simple HTML5 doctype as soon as possible.
HTML Tag Namespace
XML namespaces are used for providing uniquely named elements and attributes in an
XML document. They are defined in Namespaces in XML, a W3C recommendation. An
XML instance may contain element or attribute names from more than one XML vocabulary.
If each vocabulary is given a namespace then the ambiguity between identically
named elements or attributes can be resolved.
Because XHTML is a blend of XML and HTML, a namespace is also assumed. While
HTML4 and earlier pages can use just the plain tags, the opening HTML
tag in all XHTML documents uses namespace information. Important validation note:
This opening HTML tag must abut the end of your doctype, not be tabbed down to the
next line in your code. Otherwise, the W3C Validator doesn’t recognize the HTML opening
tag properly, and you will get errors.
HTML5, however, does not require a stated namespace.
Head Section Charset
A character encoding (charset) is a method of converting bytes into characters, which addresses
the issue of what abstract characters may be part of an HTML document. To validate
or display an HTML/XHTML document, a program must choose a character encoding.
The basic charset is UTF-8, which is compatible with ASCII characters. Because the ISO
character-sets are limited in size, and are not compatible in multilingual environments,
the Unicode Consortium developed the Unicode Standard, which covers all the characters,
punctuations, and symbols in the world. We will focus on UTF-8, especially since it
is also the charset recommended for HTML5.
ISO-8859-1 is also commonly used, since it allows for characters to be used from North
America, Western Europe, Latin America, the Caribbean, Canada, and Africa. However,
it has limits compared to UTF-8.
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