What do we call a system where all processing is done at a server or mainframe without local processing?

A system where all processing is performed at a server or mainframe without local processing is referred to as Dumb Terminals. In this setup, the terminals do not have the capability to execute software applications or perform complex computations independently; instead, they rely entirely on the server for all processing tasks. Users interact with the mainframe via a terminal interface, and all the processing power and storage is centralized, allowing for streamlined management of applications and data.

This architecture contrasts with other models, where processing abilities vary. For instance, thin clients have a minimal processing capacity but still rely on servers for most tasks, while networked workstations typically have local processing power and can execute applications independently of a central server. Fat clients possess significant local processing capabilities, allowing them to perform complex computations without needing constant server interaction. Thus, dumb terminals represent a distinct model characterized by their complete dependence on a central processing unit.