A dumb terminal is a monitor that does not process input on its own and instead sends all requests for data to a central computer. Dumb terminals are often used in office networks as they can be inexpensive and secure.
Dumb terminals may also be called glass ttys because they have a minimally addressable cursor but no on-screen editing or other features normally associated with a smart terminal. This is a term that is frequently misunderstood, and there are many conflicting definitions of what a dumb terminal is.
Smart terminals are terminals that can process information locally and then send that information to another device (usually a more powerful processor) to do further processing. These include ATM machines and point-of-sale terminals.
Historically, this was the case with mainframe terminals because they had very little internal processing capability and essentially sent their keystrokes to a central controller that then interpreted them. However, UNIX and VAX minicomputers introduced the concept of a separate IO processor that allowed them to do a lot more local processing without affecting the central control. The term “dumb” was then inverted because UNIX and VAX computers were able to deliver a much more interactive user interface.
One of the ways that this inversion worked was that because a UNIX or VAX machine was notified of every keystroke, they were able to process it much faster than a dumb terminal could do. In this way, they became intelligent terminals and the term “dumb” was dropped.
A dumb terminal may be a display monitor that is plugged into a network router or a more complex system with an actual tower computer that is connected to the internet. Dumb terminals are a popular choice in business networks because they are inexpensive, easy to deploy, and can be controlled remotely.
There is some confusion about what makes a terminal “smart.” Some experts believe that the ability to load real programs onto the screen, whether through punch cards, punched paper tape, or direct binary load (but not with an alternate character set) qualifies. Others claim that the ability to mark fields and enforce some validation qualifies.
In any event, most people agree that if the terminal can run a real program locally, it is smart. This can include BASIC, assembler, direct binary load, or even Javascript downloaded from a web browser.
Some terminals have additional scripted interactions, such as opening doors or turrets in high-security settings like Vaults and military bases. These can be rigged to trigger traps, launch rockets or ICBMs, and modify hologram defenses.
These can be a useful tool in game as well, giving XP for hacking and lockpicking as long as the terminal is not locked first. This is an advantage in the Fallout series, as it can be used to open safes and doors allowing for a player to use both hacking and lockpicking at once.
In a dungeon setting, this can also be a good way to gain more XP from lockpicking by hacking the terminal before unlocking the door or safe. This is especially helpful when there are ghouls in the area and one cannot gain XP by unlocking them.