Beginning C# 2008 Objects: From Concept to Code

7.2. Three Distinguishing Features of an OOPL

We now defined all three of the features required to make a language truly object-oriented:

• (Programmer creation of) User-defined types

• Inheritance

• Polymorphism

By way of review, here is a summary of the benefits of each of these language features.

Programmer creation of user-defined types

• Provides an intuitive way to represent real-world objects, resulting in easier-to-verify requirements.

• Classes are convenient units of reusable code, which means less code to write when building an application.

• Through encapsulation, we minimize data redundancy—each item of data is stored once, in the object to which it belongs—and therefore lessen the chance of data integrity errors.

• Through information hiding, we ...