What is Filemaker PRO and how to use it

FileMaker Pro is a cross-platform relational database application from FileMaker Inc., formerly Claris, a subsidiary of Apple Inc. It integrates a database engine with a GUI-based interface, allowing users to modify the database by dragging new elements into layout, screens or forms. Current versions are:
FileMaker Pro 11, FileMaker Pro Advanced 11, FileMaker Server 11, FileMaker Server Advanced 11, and FileMaker Go for iPhone and iPad. FileMaker evolved from a DOS application, but was then developed primarily for the Apple Macintosh. Since 1992 it has been available for Microsoft Windows as well as Mac OS, and can be used in a heterogeneous environment.