Definitions :: 2005 AISICS

Hypertext: Words marked up with tags so clicking on one word can lead to different text, essentially turning two-dimensional documents into 3D.
Language: A computer programming language. A set of instructions that directs a computer to perform specific tasks.
HTML: HyperText Markup Language. A computer language where content is marked up with tags, the result which is hypertext which is interpreted by a browser as a web page.
XML: eXtensible Markup Language. XML is a simple, very flexible text format originally designed to meet the challenges of large-scale electronic publishing, XML is also playing an increasingly important role in the exchange of a wide variety of data on the Web and elsewhere.
XHTML: eXtensible HyperText Markup Language. XHTML 1.0 isa reformulation of HTML 4 as an XML 1.0 application. The semantics of the elements and their attributes are defined in the W3C Recommendation for HTML 4. These semantics provide the foundation for future extensibility of XHTML.
DTD: Document Type Definition. The purpose of a DTD is to define the legal building blocks of an XML document. It defines the document structure with a list of legal elements.
CSS: Cascading Style Sheets. CSS is a simple mechanism for adding style (e.g. fonts, colors, spacing) to Web documents. Style sheets describe how documents are presented on screens, in print, or perhaps how they are pronounced.
W3C: World Wide Web Consortium. The W3C develops interoperable technologies (specifications, guidelines, software, and tools) to lead the Web to its full potential. W3C is a forum for information, commerce, communication, and collective understanding.

Content: When we refer to content, we mean the material for which people are reading the web site. Basically, the words and pictures on the screen. The content is independent of any formatting or presentation concerns — just the words.
Tag: Tags are how HTML is marked up. You add tags to content by typing in tags around the parts of the document you want to make look different. For example, if you want something to appear in bold face, you surround it with the tags for begin bold face and end bold face, which are and respectively. So if you want the words Computer Science to appear in bold face, you would type Computer Science. With a half a dozen tags, you can make a document that looks like a word-processed page. With a few dozen more tags you can add graphics and get into some pretty fancy formatting. The combination of regular words (content) and tags is called markup. The content is what you want your readers to see, the markup is how you make it so it looks like you want it to look.
Markup: Content + Tags. You can see the markup of any web page by selecting view source from the view menu.

Structure: When HTML was created, the authors had specific intentions for the <tags>. The tags' names were indicative of what the content meant; they added meaning to the content. When we use meaningful (structured) markup we add meaning to our content without concerning ourselves with the presentation of that meaning. When we use instead of we tell the browsers that these words should appear or sound more important than the other words and it is up to the browsers (with the help of our style sheets) to render that meaning. This is also called semantic markup and the more we use it, the closer we get to separating content from presentation.
Semantics: Meaning in language.
Layout: The positioning of all the parts of a web page on that page.
Style: Fonts, colors, spacing.
Presentation: When we speak of presentation we mean the entire look of a web page. Layout + Style. The colors, the size of the type, the positioning of the margins and pictures.