Web page

A screenshot of Wikimedia Commons, a web page

A web page (or webpage) is a web document that is suitable for the World Wide Web and the web browser. A web browser displays a web page on a monitor or mobile device. The web page is what displays, but the term also refers to a computer file, usually written in HTML or comparable markup language. Web browsers coordinate the various web resource elements for the written web page, such as style sheets, scripts, and images, to present the web page.

Typical web pages provide hypertext that includes a navigation bar or a sidebar menu to other web pages via hyperlinks, often referred to as links.

On a network, a web browser can retrieve a web page from a remote web server. On a higher level, the web server may restrict access to only a private network such as a corporate intranet or it provides access to the World Wide Web. On a lower level, the web browser uses the Hypertext Transfer Protocol (HTTP) to make such requests.

A static web page is delivered exactly as stored, as web content in the web server's file system, while a dynamic web page is generated by a web application that is driven by server-side software or client-side scripting. Dynamic website pages help the browser (the client) to enhance the web page through user input to the server.

Color, typography, illustration, and interaction

Web pages usually include information as to the colors of text and backgrounds and very often also contain links to images and sometimes other types of media to be included in the final view. Layout, typographic and color-scheme information is provided by Cascading Style Sheet (CSS) instructions, which can either be embedded in the HTML or can be provided by a separate file, which is referenced from within the HTML. The latter case is especially relevant where one lengthy stylesheet is relevant to a whole website: due to the way HTTP works, the browser will only download it once from the web server and use the cached copy for the whole site.

Images are stored on the web server as separate files, but again HTTP allows for the fact that once a web page is downloaded to a browser, it is quite likely that related files such as images and stylesheets will be requested as it is processed. An HTTP 1.1 web server will maintain a connection with the browser until all related resources have been requested and provided. Web browsers usually render images along with the text and other material on the displayed web page.

Dynamic behavior

Main article: dynamic web page

Client-side computer code such as JavaScript or code implementing Ajax techniques can be provided either embedded in the HTML of a web page or, like CSS stylesheets, as separate, linked downloads specified in the HTML. These scripts may run on the client computer, if the user allows.

Browsers

Main article: Web browser

A web browser can have a Graphical User Interface, like Internet Explorer, Mozilla Firefox, Chrome, and Opera, or can be text-based, like Lynx or Links.

Web users with disabilities often use assistive technologies and adaptive strategies to access web pages.[1] Users may be color-blind, may or may not want to use a mouse perhaps due to repetitive stress injury or motor neurone problems, may be deaf and require audio to be captioned, may be blind and using a screen reader or braille display, may need screen magnification, etc.

Disabled and able-bodied users may disable the download and viewing of images and other media, to save time, network bandwidth or merely to simplify their browsing experience. Users of mobile devices often have restricted displays and bandwidth. Anyone may prefer not to use the fonts, font sizes, styles and color schemes selected by the web page designer and may apply their own CSS styling to the page. The World Wide Web Consortium (W3C) and Web Accessibility Initiative (WAI) recommend that all web pages should be designed with all of these options in mind.

Elements

A web page, as an information set, can contain numerous types of information, which is able to be seen, heard or interacted with by the end user:

Perceived (rendered) information:
  • Textual information: with diverse render variations.
  • Non-textual information:
  • Interactive information: see interactive media.
    • For "on page" interaction:
      • Interactive text: see DHTML.
      • Interactive illustrations: ranging from "click to play" images to games, typically using script orchestration, Flash, Java applets, SVG, or Shockwave.
      • Buttons: forms providing an alternative interface, typically for use with script orchestration and DHTML.
    • For "between pages" interaction:
      • Hyperlinks: standard "change page" reactivity.
      • Forms: providing more interaction with the server and server-side databases.
Internal (hidden) information:
Note: on server-side the web page may also have "Processing Instruction Information Items".

The web page can also contain dynamically adapted information elements, dependent upon the rendering browser or end-user location (through the use of IP address tracking and/or "cookie" information). From a more general/wide point of view, some information (grouped) elements, like a navigation bar, are uniform for all website pages, like a standard. This kind of "website standard information" are supplied by technologies like web template systems.

Rendering

Web pages will often require more screen space than is available for a particular display resolution. Most modern browsers will place a scrollbar (a sliding tool at the side of the screen that allows the user to move the page up or down, or side-to-side) in the window to allow the user to see all content. Scrolling horizontally is less prevalent than vertical scrolling, not only because such pages often do not print properly, but because it inconveniences the user more so than vertical scrolling would (because lines are horizontal; scrolling back and forth for every line is much more inconvenient than scrolling after reading a whole screen; also most computer keyboards have page up and down keys, and many computer mice have vertical scroll wheels, but the horizontal scrolling equivalents are rare). When web pages are stored in a common directory of a web server, they become a website.

A website will typically contain a group of web pages that are linked together, or have some other coherent method of navigation. The most important web page to have on a website is the index page. Depending on the web server settings, this index page can have many different names, but the most common are index.html. When a browser visits the homepage for a website, or any URL pointing to a directory rather than a specific file, the web server will serve the index page to the requesting browser. If no index page is defined in the configuration or no such file exists on the server, either an error or directory listing will be served to the browser. A web page can either be a single HTML file or made up of several HTML files using frames or Server Side Includes (SSIs).

Frames have been known to cause problems with web accessibility, copyright,[2] navigation, printing and search engine rankings, and are now less often used than they were in the 1990s.[3] Both frames and SSIs allow certain content which appears on many pages, such as page navigation or page headers, to be repeated without duplicating the HTML in many files. Frames and the W3C recommended an alternative of 2000, the <object> tag,[3] also allow some content to remain in one place while other content can be scrolled using conventional scrollbars. Modern CSS and JavaScript client-side techniques can also achieve all of these goals and more.

When creating a web page, it is important to ensure it conforms to the World Wide Web Consortium (W3C) standards for HTML, CSS, XML and other standards. The W3C standards are in place to ensure all browsers which conform to their standards can display identical content without any special consideration for proprietary rendering techniques. A properly coded web page is going to be accessible to many different browsers old and new alike, display resolutions, as well as those users with audio or visual impairments.

URL

This is also called as Uniform Resource Locator (URL).Typically, web pages today are becoming more dynamic. A dynamic web page is one that is created server-side when it is requested, and then served to the end-user. These types of web pages typically do not have a permalink, or a static URL, associated with them. Today, this can be seen in many popular forums, online shopping, and even on Wikipedia. This practice is intended to reduce the amount of static pages in lieu of storing the relevant web page information in a database. Some search engines may have a hard time indexing a web page that is dynamic, so static web pages can be provided in those instances.

Creation and viewing

To create a web page, a text editor or a specialized HTML editor is needed. In order to upload the created web page to a web server, traditionally an FTP client is needed.

The design of a web page is highly personal. A design can be made according to one's own preference, or a premade web template can be used. Web templates let web page designers edit the content of a web page without having to worry about the overall aesthetics. Many people turn to all-in-one sites for web domain purchases, web hosting service and templates to build customised websites. Web publishing tools such as Tripod and Wordpress offer free page creation and hosting up to a certain size limit. Other ways of making a web page is to download specialized software, like a Wiki, CMS, or forum. These options allow for quick and easy creation of a web page which is typically dynamic.

In order to graphically display a web page, a web browser is needed. This is a type of software that can retrieve web pages from the Internet. Most current web browsers include the ability to view the source code. Viewing a web page in a text editor will also display the source code.

Pages are frequently found with assistance from a search engine.

Saving

While one is viewing a web page, a copy of it is saved locally; this is what is being viewed. Depending on the browser settings, this copy may be deleted at any time, or stored indefinitely, sometimes without the user realizing it. Most GUI browsers provide options for saving a web page more permanently. These may include:

Most operating systems allow applications such as web browsers not only to print the currently viewed web page to a printer, but optionally to "print" to a file that can be viewed or printed later. Some web pages are designed, for example by use of CSS, so that hyperlinks, menus and other navigation items, which will be useless on paper, are rendered into print with this in mind. Sometimes, the destination addresses of hyperlinks may be shown explicitly, either within the body of the page or listed at the end of the printed version. Web page designers may specify in CSS that non-functional menus, navigational blocks and other items may simply be absent from the printed version.

See also

References

  1. ↑ "How People with Disabilities Use the Web". W3C. 5 May 2005. Retrieved 2009-05-01.
  2. ↑ Tysver, Dan (1996–2008). "Linking and Liability — Problems with Frames". Minneapolis, USA: Beck & Tysver. Retrieved 2009-05-01.
  3. 1 2 "HTML Techniques for Web Content Accessibility Guidelines 1.0 - Frames". W3C. 6 November 2000. Retrieved 2009-05-01. In the following sections, we discuss how to make frames more accessible. We also provide an alternative to frames that uses HTML 4.01 and CSS and addresses many of the limitations of today's frame implementations.
  4. ↑ Santambrogio, Claudio (10 March 2006). "…and one more weekly!". Opera Software. Retrieved 2009-05-15.

Further reading

This article is issued from Wikipedia - version of the Monday, February 08, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.