Programming languages and environments
The use of HTML programming languages extend beyond the capabilities of the Web. They are used to write software, process web forms, fetch and display data, and perform all kinds of advanced functions. It is difficult to talk about these languages without getting into too much technical jargon, but here is an attempt. What follows is a brief guide to some of the more common languages in use on the Web today.
CGI (Common Gateway Interface) refers to a specification by which programs can communicate with a Web server. A CGI program, or script, is any program designed to process data that conforms to the CGI specification. The program can be written in any programming language, including C, Perl, and Visual Basic Script (VBScript). In the early days of the Web, CGI scripts were commonly used to process a form on a Web page. Perl is popular with Google, and is also the language of the Movable Type blog platform.
Active Server Pages (ASP): Developed by Microsoft, ASP is a programming environment that processes scripts on a Web server. The programming language VBScript is often used for the scripting. Lightweight programs can be written with this language. Active Server Pages, end in the file extension. Asp. For an example, check out the Databases and Indexes at the University at Albany Libraries.
. NET framework: Also developed by Microsoft, this development framework is a more powerful one than ASP for writing applications for the Web. Programming languages include C + and VB.Net. ASP.Net is a related environment, producing pages with the file extensions. Aspx. The Microsoft site is a good example of a site created with the. NET framework.
PHP: This is another server-based language. It is frequently the language used to write open source (eg, non-profit, community-created) programs found on the Web, including MediaWiki (the software that runs the Wikipedia), and the popular blog software WordPress. While PHP functionality can be installed on Windows servers, it is native to the Linux server environment and commonly used there.
Java / Java Applets: Java is a programming language similar to C + +. Developed by Sun Microsystems, the aim of Java is to create programs that will be platform independent. The Java motto is, "Write once, run anywhere." A perfect Java programs should work equally well on a Windows, Apple, Unix, or Linux servers, and so on, without any additional programming. This goal has yet to be realized. Java can be used to write applications for both Web and non-Web use.
Web-based Java applications are usually in the form of Java servlets. These are small Java programs fetched from within a Web page that can be downloaded from a server and run on a Java-compatible Web browser. A Web page that links to a Java servlet has the file extension. Jsp.
Web-based Java applications are usually in the form of Java servlets. These are small Java programs fetched from within a Web page that can be downloaded from a server and run on a Java-compatible Web browser. A Web page that links to a Java servlet has the file extension. Jsp.
JavaScript is a very popular programming language created by Netscape Communications. Small programs written in this language are embedded within a Web page, or fetched externally from within the page, to enhance the page's functionality. Examples of JavaScript include drop-down menus, image displays, and mouse-over interactions. The drop-down menus on the site of the UCLA Library shown below are a good
XML: XML (Extensible Markup Language) is a mark-up language that enables Web designers to create customized tags to provide functionality not available with HTML alone. XML is a language of the data structure and exchange, and allows developers to separate form from content. With XML, the same content can be formatted for multiple applications. In May 1999, the W3 Consortium announced that HTML 4.0 has been recast as an XML application called XHTML.
AJAX stands for Asynchronous JavaScript and XML. This langauge is used to create interactive Web applications. Its premise is that it sends data to the browser behind the scenes, so that when it is time to view the information, it is already "there." Google Maps is a well-known example of AJAX. A different kind of example can be found with SurfWax LookAhead, an RSS search tool that retrieves feeds as you type your search.
SQL (Structured Query Language): This is a language that Focuses on extracting data from databases. Programmers write statements called queries that retrieve data from the tables in the database. Some Web sites extensively or are created entirely from data stored in database tables. You can often tell that a SQL query has produced data on a page by the presence of a question mark (?) And a record number in the URL, as the example below illustrates.
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