In SAP, what is the main difference between classical ABAP and Object-Oriented ABAP (OOABAP), and in which situation is OOABAP especially preferred?

Introduction / Context:
ABAP is SAP's programming language used for developing applications in the SAP environment. Over time, ABAP evolved from a purely procedural language into one that supports full object-oriented features, often referred to as Object-Oriented ABAP (OOABAP). Understanding the differences between classical ABAP and OOABAP, and knowing when to apply each style, is important for SAP development and interviews.

Given Data / Assumptions:

• Classical ABAP refers to procedural ABAP programs using form routines, function modules, and report programming.
• OOABAP introduces classes, interfaces, methods, attributes, inheritance, and polymorphism.
• SAP's newer frameworks and technologies, such as Web Dynpro ABAP and many modern APIs, are designed around OOABAP.
• We want to identify both the conceptual difference and a typical situation where OOABAP is preferred.

Concept / Approach:
Classical ABAP code is structured procedurally, with global data and subroutines or function modules that operate on that data. OOABAP organizes code into classes and objects, encapsulating data and behaviour together. This makes it easier to build modular, reusable, and extensible applications. When working with complex user interfaces, framework-based development, or large, maintainable applications, OOABAP is usually the recommended approach because it integrates well with SAP's object-oriented frameworks.

Step-by-Step Solution:
1. Identify what classical ABAP offers: procedural constructs, form routines, include programs, and function modules.2. Identify what OOABAP adds: classes, methods, attributes, events, inheritance, interfaces, and polymorphism, following standard object-oriented principles.3. Recognise that SAP technologies such as Web Dynpro ABAP, Business Object layer implementations, and many framework-based enhancements expect OOABAP concepts.4. Option A states that classical ABAP is primarily procedural, while OOABAP adds full object-oriented features and is preferred for complex, reusable, and modular applications such as Web Dynpro and modern SAP frameworks. This matches real-world practice.5. Option B is clearly wrong because ABAP is not restricted to database administration and OOABAP is not used for OS development.6. Option C falsely ties each language style to specific SAP modules, which is not how ABAP usage is determined.7. Option D is wrong because there is a significant difference in programming model and syntax between classical ABAP and OOABAP.8. Therefore, Option A is correct.

Verification / Alternative check:
SAP documentation and training courses distinguish between classical report programming and object-oriented programming in ABAP. Tutorials on OOABAP show examples of defining classes using the CLASS…ENDCLASS syntax and demonstrate how these classes are used in Web Dynpro ABAP, ALV object models, and other frameworks. Project guidelines from SAP often recommend using OOABAP for new developments, confirming the preference described in Option A.

Why Other Options Are Wrong:
Option B is wrong because ABAP and OOABAP are both used for business application development, not OS or low-level system programming.Option C is wrong because the choice between procedural and OO styles is not tied strictly to a functional module like HR or MM.Option D is wrong because OOABAP introduced significant language extensions and is not simply a new name for the same style of programming.

Common Pitfalls:
Many developers who started with classical ABAP are slow to adopt OOABAP and continue writing mainly procedural code, missing out on modularity and reuse. Another pitfall is using OOABAP syntax but still designing code procedurally, without properly encapsulating behaviour and data. Understanding when and why to use OOABAP, especially in framework-based and large-scale applications, is key to writing modern SAP code.

Final Answer:
Classical ABAP is primarily procedural, while OOABAP adds classes, objects, inheritance, and polymorphism and is preferred for complex, reusable, and modular applications such as Web Dynpro and modern SAP frameworks.