REALBasic is a
RAD designed by REAL Software (http://www.realsoftware.com) to allow even those not very familiar with
MacOS programming to develop programs that prove themselves to be quite useful.
The strongest advantage point of REALBasic is the ability to easily drag-and-drop controls to design the user interface directly in the window.
Though there are many different controls, almost every control can be implemented through code, simply creating the control as an object. This allows those who are used to program in different ways to still use the program with ease.
Another nice feature is the ability to compile for MacOS Classic (9.2 and below), MacOS Carbon (X and below), and Windows. One can even import projects from Microsoft Visual Basic.
Even with the extensive library of functions and methods included, REAL Software added the ability for developers to make plugins for REALBasic, extending the functionality by adding more functions, methods, and controls.
The coding style of BASIC can be a somewhat enjoyable experience, and it makes a nice, easy first programming language for beginners while still allowing them to make powerful programs with a click of the mouse.
Making programs for the MacOS used to be an arduous task depending on the framework used, but REALBasic adds a simplicity that is very welcomed.
However, it is not without its faults. The biggest problem is that a programmer that does not check his code can cause an error that has given REALBasic a bad name. This error is a NilObjectException, which can only be caused by poor coding on the part of the programmer. This is mainly because REALBasic is used by many beginners, that need more experience. The Macintosh software market saw a lot of these programs (with errors) when REALBasic first came out...