Explain the difference between 2-tier and 3 tier client server model.

Two-tier architecture is client/server architecture, where a request to do some task is sent to the server and the server responds by performing the task. Server has the data and may also contain business logic.


Where as a three-tier or a multi tier architecture has client, server and database. Where the client request is sent to the server and the server in turn sends the request to the database. The database sends back the information/data required to the server which sends it back to the client.



Difference between Thin Client and Fat Client:

A thin client (sometimes also called a lean or slim client) is a computer or a computer program which depends heavily on some other computer (its server) to fulfill its traditional computational roles. Where as Fat Client performs these roles by it self.
In simple words fat clients has more processing capabilities and they are less dependent on the server.