A thin client is designed to be especially small so that the bulk of the data processing occurs on the server. Although the term thin client often refers to software, it is increasingly used for the computers, such as network computers and Net PCs, that are designed to serve as the clients for client/server architectures. A thin client is a network computer without a hard disk drive. They act as a simple terminal to the server and require constant communication with the server as well.
Thin Client devices for Virtual Desktop Infrastructure (VDI) are traditionally end-point devices with some type of skinny, locked-down OS. The most common type of Thin Clients run on Linux, Windows Embedded (WIN XPe/WES/WES7) and to a lesser degree Windows CE. Windows CE is deployed less frequently due to the lack of available connection broker. It is extremely difficult for a Windows Embedded Thin Client to get a virus and is impossible for a Linux Thin Client to get one. Along with being easy to install, thin clients also offer a lower total cost of ownership over desktop PCs.
Zero clients are slimmer and more cost-effective than thin clients. These are client devices that require no configuration and have nothing stored on them. Dell Wyse is among the leaders in zero client technology.
Instead of an operating system, Zero Clients have a highly tuned onboard processor specifically designed for one possibly three VDI protocols (PCoIP, HDX, or RemoteFX). Most of the decoding and display processes take place in dedicated hardware and therefore are more efficient than using a software client and a standard CPU and GPU setup as with a Thin Client. Zero Clients have boot up speeds of just a few seconds and are immune to viruses, decreasing the overall downtime of the device and increasing the productivity to the end-user. The Zero Client device requires very little maintenance and rarely needs an update unless there is a significant change/enhancement to the VDI protocol or the occasional BIOS related update.