Server Side Web Development

How Web Pages Are Delivered To The Viewer

A Web page is stored as a text file on a web server and downloaded to a viewer's computer by a web browser when a link is clicked or the address of the page is entered into the address bar at the top of the browser.

Browsers want HTML documents

The browser will expect an HTML document which it can interpret and display to the viewer. All web pages will normally be HTML documents but whether these are stored or generated live doesn't matter to the downloading browser.

Static and Dynamic Pages

HTML documents may be either static pages hard coded by the developer at the time of design or dynamic, that is with some or all content, constructed on the server at the time the page is requested by the browser.

To generate dynamic pages the server will run a script or program which will write the HTML directly to the requesting browser. Such dynamically generated pages are produced by scripts or applications using a variety of parameters to create the requested page and are often populated with content from a data source on the server. These server side techniques allow for the creation of full blown web applications such as online stores, web forums and discussion groups etc.

Web Development Technologies

There are a number of technologies used to produce web applications, amongst the most well known are PHP, ASP, Perl and ASP.Net

PHP

PHP originally stood for 'Personal Home Page' but as the language has evolved into a highly sophisticated application development tool the original name is no longer appropriate and the acronym is now held to represent a recursive representation of the term 'Hypertext Preprocessor' This change of name to suit the need may seem a little odd but is just an example of how the rapid evolution of internet technologies necessitates the constant re-evaluation of everything connected with the World Wide Web.

PHP is a scripted language interpreted by an application called on the web server when a page with '.php' as an extension is called by a client browser. The application follows the logic of the PHP script making calls to data sources and other resources as necessary and outputs pure HTML directly to the stream delivered to the client browser. PHP a is quick, efficient language and is very popular amongst web developers who like it's combination of simplicity and extensibility allowing everything from simple scripts to full blown object oriented programming (OOP) applications to be authored depending on the needs of the web site it services. PHP is a portable language allowing scripts to be run with a minimum of alteration on the vast majority of web server operating systems.

ASP

Classic ASP is a now largely obsolete technology which uses 'Microsoft Visual Basic' as it's scripting language. ASP is simple to learn but can have trouble handling large numbers of requests (hits) for the pages it generates; it is also, by modern standards, a very slow language.
ASP is a very Microsoft orientated system and is only really suitable for running on a Windows server whereas PHP can be run on all common web server systems. ASP pages have the extension '.asp' at the end of the page URL. Although we have used ASP in the past, we at MBM Online have now ceased using this technology.

ASP.NET

ASP.NET is Microsoft's updated version of ASP and is a much faster and more robust technology allowing very high levels of sophistication and functionality to be employed by a web application. ASP.NET can be scripted using several different computer languages but most developers will use either C# or Visual Basic for there projects. ASP.NET suffers from the same lack of portability as its predecessor and needs to be run on a Microsoft web server utilizing the Microsoft .NET server extensions.

Perl

Perl is a language falling into disuse as a means of generating dynamic content on web pages as, like ASP, it is very slow. Perl is both cumbersome to write and apply requiring a CGI folder in place on the website. This is a first generation language for the web which is rapidly dwindling in popularity, giving way to PHP with that languages greater flexibility and portability.