Web Application Development: Common Technologies

This is part of a Content Management System.

 Although each of the following technologies claim superiority over the others, they all have some failry common bonds. Each requires a means by which the application environment can access data on a server (via a database), processes the code within the page on the server prior to sending it to the user as plain HTML, and is capable of creating complex dynamic web sites.

ColdFusion
A product created by Allaire Corporation of Cambridge, Mass. (in 2001, Allaire merged with Macromedia) that includes a server and a development toolset designed to integrate databases and Web pages. With Cold Fusion, a user could enter a zip code on a Web page, and the server would query a database for information on the nearest movie theaters and present the results in HTML form. Cold Fusion Web pages include tags written in Cold Fusion Markup Language (CFML) that simplify integration with databases and avoid the use of more complex languages like C++ to create translating programs.

PHP Hypertext Preprocessor is a server-side, HTML embedded scripting language used to create dynamic Web pages. In an HTML document, PHP script is enclosed within special PHP tags. Because PHP is embedded within tags, the author can jump between HTML and PHP instead of having to rely on heavy amounts of code to output HTML. And, because PHP is executed on the server, the client cannot view PHP code.

PHP was created sometime in 1994 by Rasmus Lerdorf. During mid 1997, PHP development entered the hands of other contributers. Two of them, Zeev Suraski and Andi Gutmans, rewrote the parser from scratch to create PHP version 3 (PHP3). Today, PHP is shipped standard with a number of Web servers, including RedHat Linux.

Active Server Pages ASP
A specification for a dynamically created Web page with a .ASP extension that utilizes ActiveX scripting -- usually VB Script or Jscript code. When a browser requests an ASP page, the Web server generates a page with HTML code and sends it back to the browser. So ASP pages are similar to CGI scripts, but they enable Visual Basic programmers to work with familiar tools.


Java Server Pages JSP
A server-side technology, Java server pages are an extension to the Java servlet technology that was developed by Sun as an alternative to Microsoft's ASPs (Active Server Pages). JSPs have dynamic scripting capability that works in tandem with HTML code, separating the page logic from the static elements -- the actual design and display of the page. Embedded in the HTML page, the Java source code and its extensions help make the HTML more functional, being used in dynamic database queries, for example. JSPs are not restricted to any specific platform or server.

CGI
Abbreviation of Common Gateway Interface, a specification for transferring information between a World Wide Web server and a CGI program. A CGI program is any program designed to accept and return data that conforms to the CGI specification. The program could be written in any programming language, including C, Perl, Java, or Visual Basic.

CGI programs are the most common way for Web servers to interact dynamically with users. Many HTML pages that contain forms, for example, use a CGI program to process the form's data once it's submitted. Another increasingly common way to provide dynamic feedback for Web users is to include scripts or programs that run on the user's machine rather than the Web server. These programs can be Java applets, Java scripts, or ActiveX controls. These technologies are known collectively as client-side solutions, while the use of CGI is a server-side solution because the processing occurs on the Web server.

One problem with CGI is that each time a CGI script is executed, a new process is started. For busy Web sites, this can slow down the server noticeably. A more efficient solution, but one that it is also more difficult to implement, is to use the server's API, such as ISAPI or NSAPI. Another increasingly popular solution is to use Java servlets.

ASP.NET
Is a programming framework built on the common language runtime that can be used on a server to build powerful Web applications. ASP.NET offers several important advantages over previous Web development models

What is .NET? Microsoft .NET is a set of Microsoft software technologies for connecting your world of information, people, systems, and devices. It enables an unprecedented level of software integration through the use of XML Web services: small, discrete, building-block applications that connect to each other—as well as to other, larger applications—via the Internet.