What is N-Tier architecture

Explain the N-Tier Architecture or What is N-Tier Architecture?

In n-tier architecture, in order to increase performance, we may distribute the application over different servers by putting different subsystems on different servers. In n-tier architecture, the presentation, the application processing, and the data management are logically separate processes. It is also possible that different components of presentation or database may be put on separate servers.

For example, in case of three-tier architecture, there are normally two servers that is, the database server and application server but in case of N-tier architecture,  each responsibility of the system such as database or logic may be put on more than one servers. These kinds of architectures are used in the situation in large system where the main concern is to maintain the system efficiency.