ARexx
The AmigaOS has support for the Rexx language, called ARexx (short for "Amiga Rexx"), and is a script language which allows for full OS scripting, similar to AppleScript, intra-application scripting, similar to VBA in Microsoft Office, as well as inter-program communication. Having a single scripting language for any application on the operating system is beneficial to users, instead of having to learn a new language for each application.
Programs can listen on an "ARexx port" for string messages. These messages can then be interpreted by the program in a similar fashion to a user pushing buttons. For example, an ARexx script run in an e-mail program could save the currently displayed email, invoke an external program which could extract and process information, and then invoke a viewer program. This allows applications to control other applications by sending data back and forth directly with memory handles instead of saving files to disk and then reloading.
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