HyperText Markup Language, or HTML, is a textual computer language that is used to create web pages.
HTML provides ways to incorporate, and format, digital images, video, audio, and text into a web page document.
In particular, HyperText enables web page authors to connect to locations within a document, to other pages on the same web site,
and to pages on other web sites. Markup Language is a set of codes, or tags, that identify parts
of a web page document such as divisions, headings, lists, paragraphs, and tables.
Using HTML, tags are associated, by default, with particular layout settings and font characteristics, making it easy for a novice web site
developer to author a web page. Tag attributes are available to modify default tag characteristics, and Cascading Style Sheets
(CSS) provide additional methods for customizing the appearance of modern HTML-based documents.
The HyperText Markup Language was first conceived by British scientist Tim Berners-Lee, who in 1989 proposed an Internet-based hypertext system
while working at CERN, the European Council for Nuclear Research.
He followed up his proposal in 1990 by specifying HTML and writing browser and server software.
The first public description of HTML became available in 1991,
when Berners-Lee mentioned on the Internet an anonymously-authored document entitled "HTML Tags".
This document, presumably written by Berners-Lee, listed many of the basic tags that are the foundation of subsequent HTML versions.
Recognizing a need to develop high-quality, consensus-based standards for the emerging World Wide Web,
Berners-Lee founded the World Wide Web Consortium (W3C) in 1994, in collaboration with CERN.
HTML began to take shape more formally in 1996, with the development of HTML 2.0 by the Internet Engineering Task Force's HTML Working Group.
HTML 3.2 became a W3C recommendation in January 14, 1997. HTML 3.2 added features such as applets, fonts, and tables to the HTML 2.0 standard.
HTML 4.0, which added Cascading Style Sheets (CSS), became a W3C recommendation on December 18, 1997.
This version, updated with corrections and clarifications, became a W3C standard on December 24, 1999.
On January 22, 2008, published a working draft for HTML5, which improves interoperability, specifies precise rules for handling all HTML elements,
and includes functions for embedding audio, video, graphics, client-side data, and interactive documents.
As noted above, HTML has evolved over time, and some HTML tags are rarely-used and/or deprecated.
Other tags have become available in recent years, especially in HTML5.
This section lists commonly-used HTML tags, grouped by function.
Some rarely-used or deprecated tags are not listed, but the tags listed below are widely supported by modern web browsers.
HTML Structural Markup
HTML - encloses a document and identifies it as HTML.
HEAD - defines document header information, including the title.
TITLE - defines a document title.
BASE - defines the base URL for relative URLs in a document.
LINK - defines document relationship to an external resource.
META - specifies document attributes.
BODY - encloses the main portion (body) of the document.
HTML Body Markup
ADDRESS - specifies author contact information.
BLOCKQUOTE - defines a section that contains a quotation.
BR - specifies a single line break.
DIV - specifies a division or section within a document.
H1 thru H6 - defines headings, ranging from H1 to H6.
HR - specifies a horizontal rule.
P - defines a paragraph.
PRE - defines a preformatted block of text.
DL - defines a definition list.
DT - defines a term in a definition list.
DD - defines a definition in a definition list.
LI - defines an item in an OL or UL list.
OL - specifies an ordered (numbered) list.
UL - specifies an unordered list.
B - displays text in boldface.
CITE - specifies a citation or reference to another source.
CODE - specifies text as computer source code.
DEL - indicates deleted text.
DFN - specifies a definition.
EM - defines emphasized text.
I - displays text in italics.
INS - indicates inserted text.
KBD - specifies text as keyboard input.
SAMP - specifies literal characters.
SMALL - displays text in a smaller size.
STRONG - displays strongly emphasized text.
SUB - displays subscripted text.
SUP - displays superscripted text.
U - displays text with an underline.
VAR - defines a variable.
Anchor and Link Markup
A - defines a hyperlink anchor.
IMG - inserts an image.
MAP - defines a client-side image map.
AREA - defines an area within an image map.
Table and Column Markup
TABLE - defines a data table.
CAPTION - defines a table caption or title.
TR - defines a row of table cells.
TD - defines a table cell.
TH - defines a table header cell.
THEAD - groups a set of table header rows.
TBODY - groups a set of table body rows.
TFOOT - groups a set of table footer rows.
COLGROUP - specifies attributes for multiple table columns.
COL - defines column attribute values.
FORM - defines a form for user input.
INPUT - defines an input control.
SELECT - defines a selection list in a form.
OPTION - defines an option in a selection list.
TEXTAREA - defines a multi-line text input control.
BUTTON - creates a clickable button.
LABEL - defines an input control label.
FIELDSET - specifies a set of related form fields.
LEGEND - defines a fieldset element caption.
IFRAME - displays a URL in an inline frame.
SCRIPT - specifies a client-side script.
Style Sheet Markup
SPAN - defines an inline section in a document.
STYLE - specifies document style information.
OBJECT - defines an embedded object.
PARAM - defines an object parameter.
HTML and CSS Working Together (Concept Illustration)