Multitier architecture

Multitier architecture(Q1052721) is a computing system architecture that may typically have three tiers, composed of a presentation tier, a domain logic tier, and a data storage tie.

Wikipedia Excerpts

Tiers vs. Layers

While the concepts of layer and tier are often used interchangeably, one fairly common point of view is that there is indeed a difference. This view holds that a layer is a logical structuring mechanism for the elements that make up the software solution, while a tier is a physical structuring mechanism for the system infrastructure. For example, a three-layer solution could easily be deployed on a single tier, such in the case of an extreme database-centric architecture called RDBMS-only architecture or in a personal workstation.