A modular system design where applications are divided into small, independent services, each handling a specific business function (e.g., authentication, payments, notifications).

• Enables independent deployment, scaling, and maintenance.
• Commonly built with Docker, Kubernetes, and REST/GraphQL APIs.
• Great for large, distributed, and rapidly evolving applications.

A single unified codebase where all modules—frontend, backend, and database—operate as one system.

• Easier to develop, test, and deploy for smaller teams or MVPs.
• Ideal for applications with tightly integrated components.
• Can later evolve into microservices as the project scales.