A web page is a document or information resource that is suitable for the World Wide Web and can be accessed through a web browser and displayed on a monitor or mobile device. This information is usually in HTML or XHTML format and may provide navigation to other web pages via hypertext links. Web pages frequently subsume other resources such as style sheets, scripts, and images into their final presentation.
Web pages may be retrieved from a local computer or from a remote web server. The web server may restrict access only to a private network, e.g. a corporate intranet, or it may publish pages on the World Wide Web. Web pages are requested and served from web servers using Hypertext Transfer Protocol (HTTP).
Web pages may consist of files of static text and other content stored within the web server's file system (static web pages), or may be constructed by server-side software when they are requested (dynamic web pages). Client-side scripting can make web pages more responsive to user input once on the client browser.
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 style sheet 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 style sheets will be requested as it is processed. Web browsers usually render images along with the text and other material on the displayed web page.
A web page, as an information set, can contain numerous types of information, which is able to be seen, heard or interact with the end user.
- Textual information: with diverse render variations.
- Non-textual information:
- Static images may be raster graphics, typically GIF, JPEG or PNG; or vector formats such as SVG or Flash.
- Animated images typically Animated GIF and SVG, but also may be Flash, Shockwave, or Java applet.
- Audio, typically MP3, or various proprietary formats.
- A video, WMV, RM, FLV, MPG, MOV.
- Interactive information.
- Interactive text.
- 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.
- Hyperlinks: standard “change page” reactivity.
- Forms: providing more interaction with the server and server-side databases.
- Internal (hidden) information:
- Linked Files through Hyperlink.
- Metadata with semantic meta-information, Charset information, Document Type Definition (DTD), etc.
- Diagramation and style information: information about rendered items (like image size attributes) and visual specifications, as Cascading Style Sheets (CSS).
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.