Object-oriented language alternative for Java platform; Java-like syntax, dynamically compiles to JVM bytecodes; compiler can emit bytecodes, or can be used dynamically for scripting; has features not in standard Java, from Python, Ruby, Smalltalk. Open source.
Web application framework, Groovy version of Ruby on Rails, to use in Java development. Can be standalone system that hides all configuration details, or integrates Java business logic. Simplifies much work, appeals to range of developers not only Java. Open source.
Groovy Mailing List Archive
Searchable archive of the official groovy mailing list provided by markmail.org
Groovy Wish List
Criticism, mainly of "." and "->" operators. Otaku, Cedric's weblog.
Groovy, Java's New Scripting Language
Description, with text, code samples, screenshots. O'Reilly ONJava.com.
Groovy: First Contact
Review, by enterprise developer Mike Spille. TheServerSide.com, Enterprise Java Community.
Groovy: The Birth of a New Dynamic Language for the Java Platform
Brief summary of ideas behind Groovy; by James Strachan, Radio Userland.
Java Community Process Program: JSRs: Java Specification Requests: 241
Groovy standardization page.
JavaOne 2005, Day 1: It's a Groovy Day
Substantial report on Groovy from first day of conference: text, code samples.
Wikipedia: Groovy Programming Language
Growing article, with links to many related topics.