In computing, ColdFusion is a tag-based, middleware programming language used chiefly for writing web-based applications. The language was created by JJ Allaire and his brother Jeremy Allaire, but the product is currently owned by Macromedia (to be acquired by Adobe).
Cold Fusion 1.0 was officially released on July 10th of 1995 by Allaire. The tag-based programming language used was called DBML (DataBase Markup Language) and was later renamed to CFML (ColdFusion Markup Language). Beginning with version 1.5, ColdFusion contained compatibility with C++, allowing users to develop extensions to the language. Years later, this would be the basis for ColdFusion Extension (CFX) Tags, a method of extending the ColdFusion language. Later versions of the language allowed extending the language by writing custom tags in Java and CFML itself. The product was also renamed ColdFusion (one word) - most likely to make it trademarkable - about this time. Starting in version 5.0, users could also define functions to extend the language (UDF = User Defined Function).
Meanwhile, Allaire began work on rewriting the basis of ColdFusion with Java (codenamed "Neo"), which would allow for greater portability among different platforms.
On January 16, 2001, Allaire announced that it would be merging with Macromedia. Shortly after the merger, Macromedia continued with the incremental release of ColdFusion 5.0 and in June 2002, Macromedia released Macromedia ColdFusion MX, extending the naming convention of Macromedia's line of products. However, with the release of ColdFusion 7.0, this convention was amended, rendering the product name "Macromedia Coldfusion MX 7". ColdFusion MX was completely rebuilt from the ground up and was based on the Java 2 Enterprise Edition (J2EE) platform. ColdFusion MX was also designed to integrate well with Macromedia Flash using Macromedia Flash Remoting MX.
ColdFusion has been used to write millions of webpages and is generally recognized to be the easiest rapid development language for people coming from straight HTML to learn. This is partly because it is tag based like HTML, and also because of the strong user community around ColdFusion. This includes user groups, listservs, conferences and the Fusebox and Mach-II methodologies for organizing ColdFusion code.
Besides being easy to learn, ColdFusion like JSP and ASP.NET is compiled to an intermediate format (bytecode), making it typically execute faster on the web than interpreted languages like PHP or ASP.
With the release of ColdFusion MX, the CFML language was extended to support basic OOP. Apart from the tag-based CFML syntax, ColdFusion also supports embedded scripts that can be written in a JavaScript-like language.
ColdFusion unlike competing technologies, e.g.PHP, is a commercial product but is available as a free feature-complete "developer version" from the Macromedia.com website. This allows developers to run a local copy of the complete enterprise system for local testing. In addition to ColdFusion, BlueDragon also offers a free "developers version" that has certain limitations.
More recently there have been several new companies offering CFML language engines including a freeware implementation by New Atlanta and IgniteFusion.
The ColdFusion application server can be used alongside an existing HTTP server application such as Apache or IIS, or it can serve as its own limited HTTP server for development purposes.