A webpage or web page is a document or resource of information that is suitable for the World Wide Web and can be accessed through a web browser and displayed on a computer screen.
This information is usually in HTML or XHTML format, and may provide navigation to other webpages via hypertext links.
Webpages 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. Webpages are requested and served from web servers using Hypertext Transfer Protocol (HTTP).
Webpages may consist of files of static text stored within the web server's file system (static webpages), or the web server may construct the (X)HTML for each webpage when it is requested by a browser (dynamic webpages). Client-side scriptingcan make webpages more responsive to user input once in the client browser.
Color, typography, illustration and interaction
Webpages usually include information as to the colors of text and backgrounds and very often also contain links to images and sometimes other 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 webpage 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 webpage.
Dynamic behavior
Client-side computer code such as JavaScript or code implementing Ajax techniques can be provided either embedded in the HTML of a webpage or, like CSS stylesheets, as separate, linked downloads specified in the HTML. These scripts may run on the client computer, if the user allows them to, and can provide additional functionality for the user after the page has downloaded.
Browsers
A web browser can have a Graphical User Interface, like Internet Explorer, Mozilla Firefox and Opera, or can be text-based, like Lynx.
Web users with disabilities often use assistive technologies and adaptive strategies to access webpages. 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 webpage 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 webpages should be designed with all of these options in mind.
Elements of a webpage
A webpage, as an information set, can contain numerous types of information, which is able to be seen, heard or interact by the end user:
Perceived (rendered) information:
§ Textual information: with diverse render variations.
§ Non-textual information:
- Static images on raster graphics, typically GIF, JPEG or PNG; or vector formats as SVG or Flash.
- Animated images typically Animated GIF and SVG, but also may be Flash, Shockwave, or Java applet.
- Audio, typically MIDI or WAV formats or Java applets.
- Video, WMV (Windows), RM (Real Media), FLV (Flash Video), MPG, MOV (QuickTime)
§ Interactive information: more complex, glued to interface; see dynamic webpage.
- For "on page" interaction:
§ Interactive text: see DHTML.
§ Interactive illustrations: ranging from "click to play" image to games, typically using script orchestration, Flash, Java applets, SVG, or Shockwave.
§ Buttons: forms providing 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:
§ Comments
§ Linked Files through Hyperlink (Like DOC,XLS,PDF,etc).
§ 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).
§ Scripts, usually JavaScript, complement interactivity and functionality.
The webpage 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. These kind of "website standard information" are supplied by technologies like web template systems.
URL
Typically, webpages today are becoming more dynamic. A dynamic webpage is one that is created server-side when it is requested, and then served to the end-user. These types of webpages 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 webpage information in a database. Some search engines may have a hard time indexing a webpage that is dynamic, so static webpages can be provided in those instances.
Viewing a webpage
In order to graphically display a webpage, a web browser is needed. This is a type of software that can retrieve webpages from the Internet. Most current web browsers include the ability to view the source code. Viewing a webpage in a text editor will also display the source code, not the visual product.
Creating a webpage
To create a webpage, a text editor or a specialized HTML editor is needed. In order to upload the created webpage to a web server, traditionally an FTP client is needed.
The design of a webpage 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 webpage designers edit the content of a webpage without having to worry about the overall aesthetics. Many people publish their own webpages using products like Geocities from Yahoo, Tripod, or Angelfire. These web publishing tools offer free page creation and hosting up to a certain size limit.
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