REEM ALMOTIRI Information Technology Department Majmaah University

Lecture 7

The HTML meta Element Metadata is information about data. Metadata will not be displayed on the page. The metadata can be used by browsers (how to display content or reload page), search engines (keywords), or other web services. The tag provides metadata about the HTML document. Meta elements are typically used to specify page description, keywords, author of the document, last modified, and other metadata.

Search services Originally there were two kinds of search services on the Web: "Search engine" and “Search directory" Search engine Google and AltaVista are all forms of search engines. These search engines write programs known as robots, crawlers and/or spiders that have the following functions: (1) to locate Web pages, (2) to read the contents of the Web pages (3) report its findings back to the search engine's indices or databases. Many search engines update their index either on a bi- monthly or monthly basis.

Search Directory Yahoo!, Open Directory Project (dmoz.org), Gipsy are forms of Web directories. These directories use human editors to review sites that are submitted for submission to the directory. Directories, unlike search engines, use a hierarchical tree structure to organize their database. Another common distinction is that a directory tends to list Web sites (root directory of a site or homepage) whereas a search engine will list Web pages (individual pages of a Web site).

The HTML meta attributes Some search engines will use the name and content attributes of the meta element to index your pages. Example 1 - Define keywords for search engines: Example 2 - Define a description of your web page: Example 3 - Define the last revision of your page: Example 4 - Refresh document every 30 seconds:

Example Describe metadata within an HTML document: profile attribute The URL in the profile attribute points to a document containing information regarding metadata.

AttributeValueDescription http-equivcontent-type content-style-type expires set-cookie others Provides an HTTP header for the information/value of the content attribute nameauthor description keywords generator revised others Provides a name for the information in the content attribute

ValueDescription authorDefines the author of the document. Example: copyrightDefines copyright information of the document. Example: descriptionSearch engines can pick up this description to show with the results of searches. Example: distributionDeclares whether the document is available to the web or on an intranet. Example: expiresSpecifies the date and time when the page expires. Example: keywordsInforms search engines what your site is about. Example: ownerDefines the owner of the page or site refreshThe document will display for a specified amount of time before refreshing or switch to a new URL. Example:

ValueDescription content- language Specifies the natural language(s) of the document (used by search engines to categorize pages by language). Example: content-typeSpecifies the character set for the contents of the document. Example: dateSpecifies the date and time when the page was created. Example: last-modifiedSpecifies the last modification date. Example: locationRedirects the visitor to another location. Example: