true
'''REALbasic''' (or '''RB''') is a BASIC compiler for Windows, Mac OS, and Linux, made by [http://www.xojo.com/ Xojo, Inc.] It has its own IDE, and projects are saved to a proprietary binary format. Unlike most BASICs, REALbasic is heavily object-oriented.
As of June 2013, the language, IDE, and company have been re-branded as Xojo.
REALbasic is not compatible with other BASICs, for the most part; examples from other BASICs usually have to be completely rewritten to work in RB.
The Wikipedia article has lots of information about REALbasic's history, capabilities, and features.