is used to execute a process (executable, batch file, script, etc.) on the server. can save any generated output to a file or write it to the screen, and so many of us would wrap calls in between and tags so as to save generated output in a variable. As of ColdFusion MX 6.1 this is no longer necessary. has a new attribute named VARIABLE, and if used the generated content will be written to the specified variable name.