It is the version 6.5 of Netbeans IDE for java application development.
NetBeans refers to both a platform framework for Java desktop applications, and an integrated development environment (IDE) for developing with Java, JavaScript, PHP, Python, Groovy, C, C++, Scala, Clojure, and others. The NetBeans IDE 7.0 no longer supports Ruby and Ruby on Rails.
The NetBeans IDE is written in Java and can run anywhere a JVM is installed, including Windows, Mac OS, Linux, and Solaris.