Customer Facing Applications is business software hosted on your machines customers can use through the internet or mobile networks to interact with your company. Some examples can be found here.
Progress Development Books
The following books published by Amduus can aid programmers with enhancing their skills and becoming familiar with a variety of Progress technologies.
Programming Standards can help your organization create and maintain software that is quicker to change, easier to change, and cheaper to change to meet changing business conditions:

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Object Oriented Programming is a new development in the Progress technology world. This book provides a more example oriented discussion of developing in the OOABL than the Progress provided books. It uses the basic data structures from computer science and then leads off from there into more information:

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The Progress E-Zines are a collection of papers written by people in the Progress development community covering a wide variety of Progress development topics. They are broken out into these three volumes. (These are available for free in PDF format at a variety of places on the web, but it is nice to have a bound printed copy.)

