The capabilities of the Internet have been enhanced and extended by using programming languages with HTML. These languages have been responsible for the dynamic and interactive nature of the Net. New languages and language extensions are being developed to increase the usability of the Internet. Here I will look at some of the important languages that have shape the Internet over the years.
CGI
The Common Gateway Interface (CGI) has been around for a long time. It allows the web server software to communicate with other programs running on the server. These external programs are called CGI scripts or CGI program and are usually written in Perl or ‘C’. CGI programs are generally used to process information submitted via a form on a web page by a visitor. For example, you might search for the word ‘cars’ on a web site. The server receives your request, passes it to the CGI program. The program then looks up a database and responds with the appropriate result formatted in HTML code.
JavaScript/Jscript
JavaScript is a programming language, which runs on the browser. It was developed by the same folks who gave us Netscape and was first implemented in version 2 of the browser. Jscript is Microsoft’s implementation of JavaScript for the Internet Explorer. By the by, JavaScript is not related to Java; this is just a clever marketing ploy by Netscape Communications. It was initially called Livescript but when Sun Microsystems released Java and it got a lot of popularity, Netscape renamed their scripting language.
JavaScript runs on the browser (client) and does not require any server software. Thus, it is a client-side scripting language. Since all execution takes place on the browser, JavaScript is responsible for most of the interactivity on a web page. Image change or text color change on mouse over, creating mouse trails are all possible through JavaScript. The language has also been widely used for basic form validation. This seems logical, as it is better to validate a form on the client side than to make several trips to the server. JavaScript is commonly embedded inside the HTML page and is thus visible to the visitor.
Java
Developed by Sun Microsystems, Java is a very powerful, object-oriented language. A lot many platform dependency issues have been ironed out with the advent of Java. Thus, Java programs for, say, Unix can be made to run on Windows or the Mac system with little or no effort. Much development is taking place on the Java front with new arrivals like Java Beans, Extended Java Beans, and Java applications for various databases and XML. Using the Java Server one can also develop dynamic Java Server Pages (JSP).
Java can be most commonly seen on the Internet in the form of applets embedded in an HTML page. Applets are small Java programs that run on a Java compatible browser.
VBScript
VBScript is a client-based language that runs only on the Internet Explorer (and quite naturally, has been developed by Microsoft). Though, the browser market share of Internet Explorer has steadily risen and overtaken that of Netscape, it is still too early to use VBScript as a client side language for your pages on the Internet. I would prefer to use JavaScript as it runs on both Netscape and the Internet Explorer. However, when developing Active Server Pages (discussed below) it is easier to code in VBScript.
ASP
Active Server Pages is a technology promoted by Microsoft. The ASP utilizes some special tags, which can be embedded in the HTML code, to generate dynamic web pages. ASP scripts run on the server, typically, the IIS on Windows NT. ASP pages carry the .asp extension that differentiates them from plain HTML pages and instructs the web server to pass the pages through the ASP interpreter. You can use VBScript, JavaScript/Jscript or a combination of the two to write ASP pages. The great advantage in using ASP is the ease of maintenance of the web site. However, the downslide is that you become too dependent on Microsoft technologies.
PHP
Open source, great development environment – PHP is a cult. This has been the answer of open source programmers to ASP from Microsoft. PHP not only carries all the goodness of ASP but also is more secure and handles databases more easily. It is a known fact that PHP on Apache Web server runs faster than ASP. PHP code is embedded inside the HTML page and can link to databases to generate dynamic HTML content.
XML
The eXtensible Markup Language is a web page developing language that enables programmers to create customized tags. These customized tags can provide the much-needed functionality not available with HTML. XML documents can be accessed using JSP, PHP etc.
There are many other languages on the Internet such as Python, VRML (Virtual Reality modeling Language), awk etc., which I have not discussed here. You can search for them on your favorite search engine.
Manish Sharma has been involved in web development since 1996. He heads
SimplyGraphix.com, a web development and advertising company in India, which
has successfully developed and promoted sites in real estate, insurance,
biotechnology/pharmaceutical, medical, software, medical, education, online
gaming/contests, financial and web portal industries.
He also runs Fontmagic.com, one of the largest font archives in the world,
and Webdevelopersnotes.com, an online resource for web developers.
