The Symbolic Stream Generator (or SSG) is a software productivity aid by Unisys

Unisys

Unisys Corporation , headquartered in Blue Bell, Pennsylvania, United States, and incorporated in Delaware, is a long established business whose core products now involves computing and networking.-History:...

 for their mainframe computer

Mainframe computer

Mainframes are powerful computers used primarily by corporate and governmental organizations for critical applications, bulk data processing such as census, industry and consumer statistics, enterprise resource planning, and financial transaction processing.The term originally referred to the...

s of the former UNIVAC 1100/2200 series

UNIVAC 1100/2200 series

The UNIVAC 1100/2200 series is a series of compatible 36-bit computer systems, beginning with the UNIVAC 1107 in 1962, initially made by Sperry Rand...

.

SSG is used to generate RUN-Streams (corresponding to IBM's Job Control Language

Job Control Language

Job Control Language is a scripting language used on IBM mainframe operating systems to instruct the system on how to run a batch job or start a subsystem....

), apply and administer symbolic changes to program source

Source code

In computer science, source code is text written using the format and syntax of the programming language that it is being written in. Such a language is specially designed to facilitate the work of computer programmers, who specify the actions to be performed by a computer mostly by writing source...

s as a form of version control, and for many other purposes.

An SSG program (i.e., its "job control script

Scripting language

A scripting language, script language, or extension language is a programming language that allows control of one or more applications. "Scripts" are distinct from the core code of the application, as they are usually written in a different language and are often created or at least modified by the...

") is called a Skeleton, and its programming language Symstream.