Final answer:
A three-tier architecture involves distributing application software across a user machine, a middle-tier server, and a backend server, with each handling specific layers of the application.
Step-by-step explanation:
In a three-tier architecture, the application software is distributed among three types of machines: a user machine, a middle-tier server, and a backend server. This architecture model divides the application into three distinct layers, each handling specific responsibilities. The user machine typically houses the client or presentation layer responsible for user interactions.
The middle-tier server acts as the application layer that processes business logic, data manipulation, and performs computations. Finally, the backend server contains the data storage layer, where databases and data management systems reside. Each tier operates independently but communicates with the others, often via a network, to complete tasks. This structure improves scalability, manageability, and security compared to traditional monolithic architectures. The backend server stores and manages the data associated with the application. This architecture allows for easier scalability, as the load can be distributed among multiple machines, and enhances security by separating the application's logic and data.