What is a Thin Client?

A thin client is a type of computer or piece of software that relies on another more powerful computer to do most of its work. Connected to a network, the thin client computer or software provides an interface through which the user communicates with a network server computer. Because the thin computer is not powerful, it is virtually useless on its own; however, when connected to a centralised network server computer, it is capable of displaying all the information that a user requires. Powerful mainframe computers, for example, can be accessed through thin client terminal emulation.

A thin client analogy you might find useful...

Here's a common movie or television scene that you should be able to recognise. In an attempt to sustain a lie, a person is coached through a conversation by a second person, who feeds them the correct lines through an earpiece. The second person is far more knowledgeable then the first person, but for one reason or another, the first person needs to be "the face" of the conversation. The movie Roxanne has probably the most famous example of this situation, when the dim-witted Chris speaks to Roxanne with the help of the witty and intelligent Charlie.

The thin client computing model can actually be compared to this scene quite congruously. In this metaphor, Roxanne is the user; Chris is the thin client computer; and Charlie is the powerful network server computer. As Roxanne interacts with Chris, Charlie listens through the earpiece and hears everything being said. Charlie then feeds Chris the appropriate lines, which Chris dutifully repeats.

In this scenario, Charlie is the one processing all the information --  he is doing all the "heavy lifting", so to speak. Chris is merely the interface through which Roxanne is communicating with Charlie.

Why use a thin client?

This begs the question, then -- why use a thin client at all? Wouldn't it be easier just to package the interface and the host computer into the one location? When this does occur, it's referred to as "fat client" computing -- here, the client has enough power to perform many functions even without a network connection.

With a thin client, the user can see all the data, tools and features they expect, but the background work is being done somewhere else on the network. If the thin client cannot connect to the network, then this background work cannot be done. This is how mainframes used by many of the world's largest corporations function; all the central data is stored on the mainframe, and can be accessed through terminal emulation software by individual employees.

The benefits of thin clients

Some of the benefits of thin client models are:

  • Reduced cost: It's generally more cost effective to have a single, centralised network server and multiple inexpensive thin client computers that connect to it than it is to have multiple expensive fat client computers.
  • Easier access: Most users aren't IT experts; they require a basic interface to perform basic tasks without having to worry about the complex processes taking place behind the scenes.
  • Higher security: Because they don't have access to the inner workings of the more powerful network server computer, inexperienced or ignorant users cannot cause breaches in security. Instead, the network server computer remains the province of IT experts who can more easily troubleshoot any problems that may occur.
  • Prolonged PC life cycle: Because hardware-intensive PC applications are no longer being run by low level PCs, the thin client PCs will last a lot longer.