All projects are broadly divided into two types of applications 2 tier and 3 tier architecture. Basically high level we can say that 2-tier architecture is Client server application and 3-tier architecture is Web based application. Below I am concentrating on the difference between Two-Tier and Three-Tier Architecture, what all advantages, disadvantages and practical example - See more at: http://www.softwaretestingclass.com/what-is-difference-between-two-tier-and-three-tier-architecture/#sthash.aLtGRx1T.dpuf