The superior tools available today only strengthen that trend. As a company develops its application sophistication from Web presence to e-commerce, the benefits extend to include everything from reducing costs to generating more revenue. This allows business managers and IT staff to understand in detail how processes work, so that computer programs can specifically follow business logic and data flows. With such high-end support tools computer applications can be developed and adapted faster, and with higher quality. Clients are PCs or workstations on which users run applications.
Clients rely on servers for resources, such as files, devices, and even processing power.
The functional modules that actually process data. This middle tier runs on a server and is often called the application server. This tier runs on a second server called the database server. The added modularity makes it easier to modify or replace one tier without affecting the other tiers. Separating the application functions from the database functions makes it easier to implement load balancing .