This document provides a comprehensive overview of web application architecture, outlining its importance, core components, various architectures (monolithic, microservices, serverless, and three-tier), and best practices for developing user-friendly applications. It emphasizes the significance of choosing the right architecture for functionality, scalability, performance, maintainability, security, user experience, and cost optimization. The article is targeted at developers, designers, and entrepreneurs looking to understand and effectively implement web application architecture.