XHTML+&+CSS

XHTML: Variant of HTML that uses the syntax of XML. Has all the same elements of HTML but syntax is slightly different. Because XHTML is an XML application you can use XML tools with it "eXtended HTML". Stricter and more extensive than HTML

Key Differences from HTML -Well formed documents -Proper nesting -MUST close elements -lowercase letters and attributes -attribute values must be in quotes

Doctypes: Tell the browser what to expect. Set up mark up declarations that define a document type for XML or HTML content. 3 types- Transitional, strict, frameset

Cascading Style Sheet: CSS Defines how web browswers should display or present XHTML elements--> colors, borders, etc -created because HTML4 tags were never intended for formatting -css lets you set the formatting instructions and maintain them separate from the content and structure of a website -3 versions--> CSS1 CSS2 CSS3
 * keeps design and content separate

CSS Syntax Selector: tells browser what element to assign the rule to (can be elements, reference id attributes and class attributes, reference to nested elements) property: tells browser what you want to change about the display of an element value: tells browser what you're changing it to rule: selector combined with one of more property and value pairings -3 ways to use it with XHTML 1. internal embedded 2. imported 3. external/linked

CSS Specificity and Order -Make sure the CSS is specific and ordered properly 1. user specified rules 2.!important rules (exclamation mark important) 3. Inline rules 4. Embedded styles 5. External Styles
 * XHTML** (eXtensible HTML): A variant of HTML that uses the syntax of XML, the Extensible Markup Language. XHTML has all the same elements (for paragraphs, etc.) as HTML, but the syntax is slightly different. Because XHTML is an XML application, one can use other XML tools with it (such as XSLT, a language for transforming XML content). @http://www.w3.org/standards/webdesign/htmlcss
 * Element**: In HTML, XHTML, and XML, an element is an individual component of a document. For (X)HTML, this means an element is one component on a Web page. All three languages are composed of a tree of elements and other nodes, such as text. Each element can have attributes specified. Elements can also have content, including other elements and text. (X)HTML and XML elements represent semantics or meaning. Most elements are written with a start tag and an end tag, with the content in between, e.g. This is the title of the page . @http://en.wikipedia.org/wiki/HTML_element
 * Attribute**: //You should have looked this one up for Keyword List #2 - if you didn't, we suggest you do so now!//
 * Document Type Definition** (DTD): A set of markup declarations that define a document type for XML or (X)HTML content. A DTD uses a terse formal syntax that declares precisely which elements and references may appear where in the document of the particular type, and what the elements’ contents and attributes are. A DTD is associated with an XML or (X)HTML document by means of a document type declaration (the DOCTYPE element). @http://en.wikipedia.org/wiki/Document_type_definition
 * (X)HTML Transitional**: A DTD that includes all HTML elements and attributes, including presentational and deprecated elements (like //font//). Framesets are not allowed; if one wants to use frames, one must use the **(X)HTML Frameset** DTD instead, which is otherwise identical to (X)HTML Transitional. @http://www.w3schools.com/tags/tag_doctype.asp
 * (X)HTML Strict**: A DTD that contains all HTML elements and attributes, but does **not** include presentational or deprecated elements (like //font//). Framesets are not allowed. Using the strict DTD is preferable and results in better (X)HTML code. @http://www.w3schools.com/tags/tag_doctype.asp
 * Deprecated**: A status applied to a computer software feature, characteristic, or practice indicating it should be avoided, typically because of it being superseded. The term is sometimes used for a feature, design, or practice that is permitted but no longer recommended. In HTML and XHTML, a deprecated element is one that may still work in Web browsers, but its use is strongly discouraged; for example, the //font// element. @https://en.wikipedia.org/wiki/Deprecation
 * CSS** (Cascading Style Sheets): Cascading style sheets define how Web browsers should display and present (X)HTML elements (e.g. colors, fonts, borders, etc.) CSS was added as of HTML 4 because HTML was never intended to contain tags for formatting a document, but to define its content and structure. CSS allows for formatting instructions to be maintained separately from the content and structure of a Web site and its pages. CSS also allows for one set of formatting instructions to be applied across a set of pages, saving much time and effort. @http://www.w3schools.com/css/css_intro.asp
 * Validation**: In the context of (X)HTML, XML, and CSS code, validation is the process of checking a document against the language and grammar (i.e. DTD) it claims to be using. Validation ensures that documents using markup languages (including HTML, XHTML, XML, and CSS) are following the rules of the language as defined by the Word Wide Web Consortium (W3C). A document that passes through the validation process with success -- by being tested with a **validator** -- is said to be **valid** HTML, XHTML, XML, or CSS. Valid code is more likely to be displayed consistently and properly in multiple Web browsers, both now and in the future. http://validator.w3.org/docs/help.html#validation_basics
 * Well-formed**: A well-formed (X)HTML document (a) has one root element that contains all of the other elements in the document; and (b) contains elements that are themselves well-formed. A well-formed element is one that is closed or terminated correctly and is not improperly nested. For example, by itself is **not** well-formed, but  is. In XHTML, by itself is **not** well-formed, as XHTML requires a closing slash: . Text is **not** well-formed because elements are improperly nested; Text is properly nested and well-formed. @http://en.wikipedia.org/wiki/Well-formed_element