An HTML document is a text file that contains the elements Internet Explorer uses to display text, multimedia objects, and hyperlinks. HTML stands for hypertext markup language. Using HTML, an author can format a document for display and add hyperlink jumps to other documents. Text that is formatted as a hyperlink can be selected by a user with the mouse. Once selected, the hyperlink jump will load the referenced document into your browser. A hyperlink and the object to which the link jumps can both be defined using HTML.
An element is the most basic part of HTML. An element consists of a start-tag, an end-tag, and the data characters enclosed by the two tags. A tag starts with a less-than (<) sign and ends with a greater-than (>) sign. An end-tag consists of the tag name immediately preceded by a slash (/). Some tags require that you always provide the matching end-tag; others allow you to omit the end-tag if the result is clear and unambiguous. For example, here is an element in HTML-a sentence that will display in bold:
<B>This sentence displays in bold.</B>
The example is an HTML element. The start-tag is <B>. The end-tag is </B>. The data characters are "This sentence displays in bold." This element, when read by Internet Explorer, will turn on bold formatting, based on the start-tag, and display the data characters in bold. The end-tag switches off the bold formatting. Many elements can be "nested" by placing an entire element inside the tags of another. For example, here is some italicized text placed inside a bold element:
<B>This sentence,<I>as written</I>, displays in bold.</B>
The <I>as written</I> element displays in both bold and italic because it is nested inside a bold element.
An element can have one or more attributes. An attribute is a parameter associated with an element that extends its meaning. Tags and attribute names are not case-sensitive, but they are typically written in uppercase to distinguish them from the data characters.
Tag | Description |
A | Stands for anchor. HREF= attribute creates hyperlinks. NAME= attribute creates a named reference. |
ADDRESS | Specifies a mailing address. |
B | Changes text to bold. See STRONG. |
BASE | Specifies a document's URL. |
BASEFONT | Sets the base font value. |
BGSOUND | Adds background sounds that play on initial load. |
BIG | Enlarges the font size. |
BLOCKQUOTE | Sets apart a quotation in text. |
BODY | Specifies the beginning and the end of the document body. See HEAD. |
BR | Inserts a line break. |
CENTER | Centers text and images. |
CITE | Indicates a citation. Used to present a book, paper, or other published source material. |
CODE | Presents a code sample. |
COL | Sets the properties of a column. |
COLGROUP | Sets the properties of one or more columns as a group. |
COMMENT | Indicates a comment. Text in a comment element does not display in a browser. |
DIR | Denotes a directory list. |
DIV | Sets a document division. Groups related elements together within a document. |
EM | Emphasizes text, usually by rendering text in italics. |
FONT | Formats the font style, size, and color. |
FORM | Denotes a form with which users enter data. See INPUT for a list of form elements. |
FRAME | Defines independent windows, or frames, within a page. See FRAMESET. |
FRAMESET | Defines layout for frames within a page. See FRAME. |
Hn | Renders text in heading style, usually with a larger font than the body text. The n is a value from 1 to 6. |
HEAD | Marks the HTML document heading. |
HR | Draws a horizontal rule. Used to separate sections. |
HTML | Denotes the file is an HTML document. |
I | Renders text in italics. |
IMG | Inserts a graphic file. |
INPUT | Specifies a form control such as a check box or radio button. See FORM. |
KBD | Indicates text to be entered at a keyboard. Appears in fixed-width and bold type. |
LI | Denotes an item in a list. Adds special character or number depending on use. See UL |
LINK | Establishes the relationship between documents. Appears only in the HEAD element. |
LISTING | Renders text in fixed-width type. |
MENU | Denotes a list of items. |
NOBR | Turns off line breaking. |
NOFRAMES | Indicates content viewable only by browsers that do not support frames. |
OL | Specifies an ordered list. Each item has a number or letter reference. See UL, LI. |
OPTION | Denotes one choice in a list box. |
P | Inserts a paragraph break and denotes a new paragraph. |
PRE | Displays text exactly as typed-with all line breaks and spacing. |
S | Renders text in strikethrough type. |
SAMP | Specifies sample text. See CODE. |
SCRIPT | Specifies the inclusion of a script. |
SELECT | Denotes a list box or dropdown list. |
SMALL | Decreases the font size. |
STRIKE | Renders text in strikethrough type. See S. |
STRONG | Emphasizes text, usually with bold. See B. |
SUB | Renders text in subscript. |
SUP | Renders text in superscript. |
TABLE | Creates a table. See TH, TR, and TD to learn how to define rows and columns. |
TD | Creates a cell in a table. |
TH | Creates a row or column heading in a table. |
TEXTAREA | Creates a box in which a user can enter and edit text. |
TITLE | Specifies a document title. Appears in the browser title bar. |
TR | Creates a row in a table. |
TT | Denotes teletype. Displays text in fixed-width type. |
U | Renders text underlined. |
UL | Formats lines of text as a bulleted list. See LI. |
JaveScript is an interpreted, object-based scripting language. Although it has fewer capabilities than full-fledged object-oriented languages like C++ and Java, JScript is more than sufficiently powerful for its intended purposes. It is not a cut-down version of any other language (it is only distantly and indirectly related to Java, for example), and it is not a simplification of anything.