A fun activity in the late 1980's and early 1990's was to write polyglot programs that ran in multiple languages, e.g. check out this one which runs in COBOL, Pascal, Fortran, C, PostScript, Linux/Unix shell script (bash, sh, csh), x86 machine language and Perl! More recently the term has resurfaced (e.g. Neal, Martin and others) in recognition of the fact that a developer no longer lives in a world dominated just by one language, e.g. COBOL, Java, C#. As a minimum, a developer must know JavaScript for AJAX sights, SQL for databases, XML, various build file dialects, various scripting languages etc., in addition to one or more mainstream languages.

This interest has been increasing lately with multiple languages being emphasised on both the JVM and the CLR. Groovy obviously supports a polyglot relationship with Java (e.g. A Groovy class can inherit from a Java class which can inherit from a Groovy class). In other cases Groovy reduces the need to introduce multiple languages because it gives you a Groovy syntax where you might otherwise have to introduce a new language, e.g. using GPath instead of introducing XPath, using datasets instead of SQL, AntBuilder instead of Ant XML files and so on. Other features just make integration with other languages a little easier, e.g. Groovy's regex, multi-line string, GString amd template support.

Groovy also has other Polyglot friendly features or integration possibilities: