Dynamic Website Development using PHP Innovation
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Wikipedia
A server-side dynamic web page is a web page whose construction is controlled by an application server processing server-side scripts. In server-side scripting, parameters determine how the assembly of every new web page proceeds, including the setting up of more client-side processing.
A client-side dynamic web page processes the web page using JavaScript running in the browser as it loads. JavaScript can interact with the page via Document Object Model, or DOM, to query page state and modify it. Even though a web page can be dynamic on the client-side, it can still be hosted on a static hosting service such as GitHub Pages or Amazon S3 as long as there isn’t any server-side code included.
A dynamic web page is then reloaded by the user or by a computer program to change some variable content. The updating information could come from the server, or from changes made to that page’s DOM. This may or may not truncate the browsing history or create a saved version to go back to, but a dynamic web page update using AJAX technologies will neither create a page to go back to, nor truncate the web browsing history forward of the displayed page. Using AJAX, the end user gets one dynamic page managed as a single page in the web browser while the actual web content rendered on that page can vary. The AJAX engine sits only on the browser requesting parts of its DOM, the DOM, for its client, from an application server. A particular application server could offer a standardized REST style interface to offer services to the web application.
DHTML is the umbrella term for technologies and methods used to create web pages that are not static web pages, though it has fallen out of common use since the popularization of AJAX, a term which is now itself rarely used. Client-side-scripting, server-side scripting, or a combination of these make for the dynamic web experience in a browser.
Classical hypertext navigation, with HTML or XHTML alone, provides “static” content, meaning that the user requests a web page and simply views the page and the information on that page.
However, a web page can also provide a “live”, “dynamic”, or “interactive” user experience. Content (text, images, form fields, etc.) on a web page can change, in response to different contexts or conditions.
There are two ways to create this kind of effect:
- Using client-side scripting to change interface behaviors within a specific web page, in response to mouse or keyboard actions or at specified timing events. In this case the dynamic behavior occurs within the presentation.
- Using server-side scripting to change the supplied page source between pages, adjusting the sequence or reload of the web pages or web content supplied to the browser. Server responses may be determined by such conditions as data in a posted HTML form, parameters in the URL, the type of browser being used, the passage of time, or a database or server state.
Web pages that use client-side scripting must use presentation technology broadly called rich interfaced pages. Client-side scripting languages like JavaScript or ActionScript, used for Dynamic HTML (DHTML) and Flash technologies respectively, are frequently used to orchestrate media types (sound, animations, changing text, etc.) of the presentation. The scripting also allows use of remote scripting, a technique by which the DHTML page requests additional information from a server, using a hidden Frame, XML Http Requests, or a web service.
Web pages that use server-side scripting are often created with the help of server-side languages such as PHP, Perl, ASP, ASP.NET, JSP, ColdFusion and other languages. These server-side languages typically use the Common Gateway Interface (CGI) to produce dynamic web pages. These kinds of pages can also use, on the client-side, the first kind (DHTML, etc.).
It is difficult to be precise about “dynamic web page beginnings” or chronology because the precise concept makes sense only after the “widespread development of web pages”. HTTP has been in use since 1990, HTML, as standard, since 1996. The web browser’s rise in popularity started with Mosaic in 1993. It is obvious, however, that the concept of dynamically driven websites predates the Internet, and in fact HTML. For example, in 1990, before general public use of the Internet, a dynamically driven remotely accessed menu system was implemented by Susan Biddle comb, who was Director of Computer Support of the USC Health Care system at the University of Southern California BBS on a 16 line TBBS system with TDBS add-on.database. Between 1995 and 1996 Cold fusion, Web Objects, PHP and Active Server Pages were introduced to the market.
The introduction of JavaScript (then known as Live Script) enabled the production of client-side dynamic web pages, with JavaScript code executed in the client’s browser. The letter “J” in the term AJAX originally indicated the use of JavaScript, as well as XML. With the rise of server side JavaScript processing, for example, Node.js, originally developed in 2009, JavaScript is also used to dynamically create pages on the server that are sent fully formed to clients.
MediaWiki, the content management system that powers Wikipedia, is an example for an originally server-side dynamic web page, interacted with through form submissions and URL parameters. Throughout time, progressively enhancing extensions such as the visual editor have also added elements that are dynamic on the client side, while the original dynamic server-side elements such as the classic edit form remain available to be fallen back on (graceful degradation) in case of error or incompatibility.
A program running on a web server (server-side scripting) is used to generate the web content on various web pages, manage user sessions, and control workflow. Server responses may be determined by such conditions as data in a posted HTML form, parameters in the URL, the type of browser being used, the passage of time, or a database or server state.
Such web pages are often created with the help of server-side languages such as ASP, ColdFusion, Go, JavaScript, Perl, PHP, Ruby, Python, WebDNA and other languages, by a support server that can run on the same hardware as the web server. These server-side languages often use the Common Gateway Interface (CGI) to produce dynamic web pages. Two notable exceptions are ASP.NET, and JSP, which reuse CGI concepts in their APIs but actually dispatch all web requests into a shared virtual machine.
The server-side languages are used to embed tags or markers within the source file of the web page on the web server. When a user on a client computer requests that web page, the web server interprets these tags or markers to perform actions on the server. For example, the server may be instructed to insert information from a database or information such as the current date.
Dynamic web pages are often cached when there are few or no changes expected and the page is anticipated to receive considerable amount of web traffic that would wastefully strain the server and slow down page loading if it had to generate the pages on the fly for each request.
Client-side scripting is changing interface behaviors within a specific web page in response to input device actions, or at specified timing events. In this case, the dynamic behavior occurs within the presentation. The client-side content is generated on the user’s local computer system.
Such web pages use presentation technology called rich interfaced pages. Client-side scripting languages like JavaScript or ActionScript, used for Dynamic HTML (DHTML) and Flash technologies respectively, are frequently used to orchestrate media types (sound, animations, changing text, etc.) of the presentation. Client-side scripting also allows the use of remote scripting, a technique by which the DHTML page requests additional information from a server, using a hidden frame, XML Http Requests, or a Web service.
The first widespread use of JavaScript was in 1997, when the language was standardized as ECMAScript and implemented in Netscape 3.
- Example
The client-side content is generated on the client’s computer. The web browser retrieves a page from the server, then processes the code embedded in the page (typically written in JavaScript) and displays the retrieved page’s content to the user.
All of the client and server components that collectively build a dynamic web page are called a web application. Web applications manage user interactions, state, security, and performance.
Ajax uses a combination of both client-side scripting and server-side requests. It is a web application development technique for dynamically interchanging content, and it sends requests to the server for data in order to do so. The server returns the requested data which is then processed by a client-side script. This technique can reduce server load time because the client does not request the entire webpage to be regenerated by the server’s language parser; only the content that will change is transmitted. Google Maps is an example of a web application that uses Ajax techniques.
Web development is the work involved in developing a website for the Internet (World Wide Web) or an intranet (a private network). Web development can range from developing a simple single static page of plain text to complex web applications, electronic businesses, and social network services. A more comprehensive list of tasks to which Web development commonly refers, may include Web engineering, Web design, Web content development, client liaison, client-side/server-side scripting, Web server and network security configuration, and e-commerce development.
Among Web professionals, “Web development” usually refers to the main non-design aspects of building Web sites: writing markup and coding. Web development may use content management systems (CMS) to make content changes easier and available with basic technical skills.
For larger organizations and businesses, Web development teams can consist of hundreds of people (Web developers) and follow standard methods like Agile methodologies while developing Web sites. Smaller organizations may only require a single permanent or contracting developer, or secondary assignment to related job positions such as a graphic designer or information systems technician. Web development may be a collaborative effort between departments rather than the domain of a designated department. There are three kinds of Web developer specialization: front-end developer, back-end developer, and full-stack developer. Front-end developers are responsible for behavior and visuals that run in the user browser, while back-end developers deal with the servers. Since the commercialization of the Web with Tim Berners-Lee developing the World Wide Web at CERN, the industry has boomed and has become one of the most used technologies ever.
PHP is a general-purpose scripting language geared toward web development. It was originally created by Danish-Canadian programmer Rasmus Lerdorf in 1993. The PHP reference implementation is now produced by The PHP Group. PHP originally stood for Personal Home Page, but it now stands for the recursive initialism PHP: Hypertext Preprocessor.
PHP code is usually processed on a web server by a PHP interpreter implemented as a module, a daemon or as a Common Gateway Interface (CGI) executable. On a web server, the result of the interpreted and executed PHP code – which may be any type of data, such as generated HTML or binary image data – would form the whole or part of an HTTP response. Various web template systems, web content management systems, and web frameworks exist which can be employed to orchestrate or facilitate the generation of that response. Additionally, PHP can be used for many programming tasks outside the web context, such as standalone graphical applications and robotic drone control. PHP code can also be directly executed from the command line.
The standard PHP interpreter, powered by the Zend Engine, is free software released under the PHP License. PHP has been widely ported and can be deployed on most web servers on a variety of operating systems and platforms.
The PHP language evolved without a written formal specification or standard until 2014, with the original implementation acting as the de facto standard which other implementations aimed to follow. Since 2014, work has gone on to create a formal PHP specification.
W3Techs reports that, as of October 2022, “PHP is used by 74.4% of all the websites whose server-side programming language we know.” PHP version 7.4 is the most used version. Support for version 7.3 was dropped on 6 December 2021.
PHP development began in 1993 when Rasmus Lerdorf wrote several Common Gateway Interface (CGI) programs in C, which he used to maintain his personal homepage. He extended them to work with web forms and to communicate with databases, and called this implementation “Personal Home Page/Forms Interpreter” or PHP/FI.
PHP/FI could be used to build simple, dynamic web applications. To accelerate bug reporting and improve the code, Lerdorf initially announced the release of PHP/FI as “Personal Home Page Tools (PHP Tools) version 1.0” on the Usenet discussion group comp.infosystems.www.authoring.cgi on June 8, 1995. This release already had the basic functionality that PHP has today. This included Perl-like variables, form handling, and the ability to embed HTML. The syntax resembled that of Perl, but was simpler, more limited and less consistent.