What is "scala"
Scala (Scalable language) is a general purpose programming language, let’s say multiparadigma, designed to express common programming patterns in a concise, elegant, and type-safe way. It incorporates features of object-oriented and functional languages. It is also fully interoperable with Java. Scala is the successor to Funnel, a language based on Join Calculus. Scala is open source software. Requires JDK version 1.4 or higher.5 Scala is a relatively new programming language. Even so, in recent years, it has conquered giant companies like Twitter and Foursquare. One of the first differences between Scala and a language like Java, is that Scala also supports the functional paradigm.
Source: http://en.wikipedia.org/wiki/Scala_(programming_language)