Software application architecture is the process of defining a structured solution that meets all of the technical and operational requirements, while optimizing common quality attributes such as performance, security, and manageability.
Start from here:
Software Architecture and Design | Microsoft Docs[
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It would help you understand:
1. "What is Software Architecture?"
2. "Key Principles of Software Architecture"
3. "Architectural Patterns and Styles"
4. "A Technique for Architecture and Design"
Few tips:
10 Ways to Improve Your Software Architecture Design[
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