Monolithic: A single, tightly integrated codebase where all components (UI, business logic, data) are bundled together. Easy to develop and deploy initially but difficult to scale and maintain as the application grows. Deployment requires redeploying the entire system, even for minor changes.

Multi-Tier: Separates the application into different layers (presentation, logic, data) that can be managed independently. Improves modularity, scalability, and maintainability. However, inter-tier dependencies still make scaling and updating less flexible than microservices.

Microservices: Breaks down the system into small, independent services, each responsible for a specific function. Allows for independent development, deployment, and scaling, offering high agility and resilience. However, it introduces complexity in managing communication, data, and deployment.