ToolTalk is an interapplication communications system developed by Sun Microsystems

Sun Microsystems

Sun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...

 (SunSoft) in order to allow applications to communicate with each other at runtime. Applications supporting ToolTalk can construct "high-level" messages and hand them off to the system's ToolTalk server, which determines the proper recipients and (after applying permission checks) forwards the message to them. Although originally available only on SunOS

SunOS

SunOS is a version of the Unix operating system developed by Sun Microsystems for their workstation and server computer systems. The SunOS name is usually only used to refer to versions 1.0 to 4.1.4 of SunOS...

 and Solaris

Solaris Operating System

Solaris is a Unix operating system originally developed by Sun Microsystems. It superseded their earlier SunOS in 1993. Oracle Solaris, as it is now known, has been owned by Oracle Corporation since Oracle's acquisition of Sun in January 2010....

, ToolTalk was chosen as the application framework for the Common Desktop Environment

Common Desktop Environment

The Common Desktop Environment is a desktop environment for Unix and OpenVMS, based on the Motif widget toolkit.- Corporate history :...

 and thus became part of a number of Unix

Unix

Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...

 distributions as well as OpenVMS

OpenVMS

OpenVMS , previously known as VAX-11/VMS, VAX/VMS or VMS, is a computer server operating system that runs on VAX, Alpha and Itanium-based families of computers. Contrary to what its name suggests, OpenVMS is not open source software; however, the source listings are available for purchase...

.

While ToolTalk had "object oriented" and "procedural" messages and a complex "pattern" structure which allowed dispatch of messages to processes based on object names, message names, and parameter types, actual desktop protocols never took full advantage of its power. Simpler pattern-matching systems like Apple Computer

Apple Computer

Apple Inc. is an American multinational corporation that designs and markets consumer electronics, computer software, and personal computers. The company's best-known hardware products include the Macintosh line of computers, the iPod, the iPhone and the iPad...

's AppleScript

AppleScript

AppleScript is a scripting language created by Apple Inc. and built into Macintosh operating systems since System 7. The term "AppleScript" may refer to the scripting system itself, or to particular scripts that are written in the AppleScript language....

 system did just as well.

The D-Bus

D-Bus

In computing, D-Bus is a simple inter-process communication open-source system for software applications to communicate with one another. Heavily influenced by KDE2–3's DCOP system, D-Bus has replaced DCOP in the KDE 4 release. An implementation of D-Bus supports most POSIX operating...

 standard has superseded ToolTalk in Unix

Unix

Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...

-like desktop environments.