Controlled Languages: An Introduction                                                                  Back|Home|Next

Technology Overview

1.0 What is a Controlled Language?
    1.1 Definitions
    1.2 Controlled Languages and Sublanguages
    1.3 Controlled Language Acceptance and Implementation

1.1 Definitions
A controlled language is a language in which terminology, syntax, and/or semantics are constrained.  In some ways, it is analogous to a style guide used by editors and writers to achieve a clear and consistent style and terminology for a particular publication.  Controlled languages have also been developed using languages other than English as the “source” language, such as German [Schactl96, Janssen96], Swedish [Almqvist96],  French [Barthe96, Barthe98], Spanish [Bustamante96], Greek [Bustamante96], and Chinese [Zhang98].  Controlled languages are used to enhance the clarity, usability, transferability, retrieveabilty, extractability, and translatability of documents.  This is achieved through increased terminological consistency and standardization, generally simplified sentence structure, and standardized document format and layout.  Controlled languages are particularly effective in commercial or industrial applications such as the authoring of user manuals or maintenance manuals, where large quantities of complex documents are generated and updated on a regular basis, and where terminology is domain specific [Farrington96, Godden96, Holmback96].  Controlled languages are also used in domains where documentation is traditionally highly complex, arcane, or poorly written, such as government, finance, and law.

1.2 Controlled Languages and Sublanguages
There is some similarity between a controlled language and a sublanguage.  A sublanguage is the language used in a specific domain, such as the special set of terms and language employed by those knowledgeable of biology, racing cars, or artificial intelligence.  For example, in the domain of computers and electronics, 'chip'  means a piece of semiconducting material, in the wood and paper industry, a 'chip' is a wood chip, a 'chip' at a British pub is a piece of fried potato.  Each of these domains has a vocabulary specific to its needs.  The critical difference is that a controlled language's terms, syntax, and semantics are actively and purposefully proscribed, generally with particular objectives in mind, while the proscriptions of a sublanguage are unspecified, and evolve naturally.

1.3 Controlled Language Acceptance and Implementation
There has been some resistance to using controlled languages because of the difficulties many authors face when first using controlled language tools.  Both the controlled language itself and the checking/correction tools must be learned, and this can be frustrating or inconvenient for engineers and technical writers [Goyvaerts96, Godden98].  However, controlled languages do meet their objectives.   Research on the subject indicates that, "with relatively complex documents, the use of SE [Simplified English] will significantly improve comprehension…(and) translations of the SE [Simplified English] versions of the procedures produced significantly higher ratings for style match and significantly fewer minor omissions than translations of the non-SE versions" [Holmback96, p. 168].

Richard Altwarg
Macquarie University Graduate Program in Speech and Language Processing
SLP803 An Introduction to Language Technology

This site last updated November 20, 2000.
Comments and corrections welcome: raltwarg@earthlink.com