A Turing Machine - Overview
Why Computer Science Stack Exchange recommends it
Computer Science Stack Exchange users link it as a concrete demonstration that Turing machines can be built physically, not just treated as a mathematical abstraction.
Recommended by 2 people across 3 different months, 2016 to 2021.
Why Stack Overflow recommends it
Stack Overflow users link it when answering questions about whether a Turing machine is real, as an example of an enthusiast actually building a physical version of the abstract device.
Recommended by 0 people across 0 different months, 2010 to 2017.
What it is
A five-minute overview of a physical Turing machine built by Mike Davey, designed to echo the look and feel of the machine described in Alan Turing's 1937 paper on computable numbers. It shows the machine reading, writing and moving along a tape according to simple rules.
What people said
Strong rec allo · 2018-12 · Computer Science Stack Exchange · on “The first Turing machine”
There are real turing machines, except that they do not have unlimited memory (and thus can only compute a limited set of programs and input values). See this amazing video of a real turing machine: [this video]
Recommends user5193682 · 2016-08 · Computer Science Stack Exchange · on “Difference between a turing machine and a finite state machine?”
I had the same doubt and I saw two very enlightning videos and one explanation on Quora as follows: A finite state machine is just a set of states and transitions. The only memory it has is what state it is in. Thus, the number of memory states is... finite. A Turing machine is a finite state machine plus a tape memory. Each transition may be accompanied by an operation on the tape (move, read, write). I have understood from it that a turing machine uses/has a a finite state machine as part of its operating procedure, plus adding some editable memory to it. Please watch also those two videos, they are enlightning! [LINK] [this video]
Recommends user5193682 · 2019-01 · Computer Science Stack Exchange · on “The first Turing machine”
Here is a video with a real Turing machine working. Its quite nice and helped me to stop seeing it as a mere mathematical model: [this video]
Cites Andrey · 2010-05 · Stack Overflow · on “Turing machine vs Von Neuman machine”
Turing model defines computational capabilities without getting deep into implementation, no one will ever create computer that will look like Turing Machine literally. (Except enthusiasts [this video] ). Turing model is not architecture . Von Neuman is guidance how to build computers. It says nothing about the computation capabilities. Depending on instruction set the produced computer may or may not be Turing complete (means can solve same tasks as Turing Machine) Functional programming (lambda calculus) is another computational model that is Turing complete but can't be natively fit into Von Neumann architecture.
Cites Burton Samograd · 2011-09 · Stack Overflow · on “Is a Turing machine a real device or an imaginary concept?”
It is a conceptual device that is not realizable (due to the requirement of infinite tape). Some people have built physical realizations of a Turing machine, but it is not a true Turing machine due to physical limitations. Here's a video of one: [this video]
Cites tadman · 2017-10 · Stack Overflow · on “If a computer can be Turing complete with one instruction what is the purpose of having many instructions?”
Remember that a Turing Machine is generally understood to be an abstract concept, not a physical thing [this video] . It's the theoretical minimal form a computer can take that can still compute anything. Theoretically. Heavy emphasis on theoretically. An actual Turing machine that did something so simple as decode an MP3 would be outrageously complicated. Programming it would be an utter nightmare as the machine is so insanely limited that even adding two 64-bit numbers together and recording the result in a third location would require an enormous amount of "tape" and a whole heap of "instructions". When we say something is "Turing Complete" we mean that it can perform generic computation. It's
Cites Andrej Bauer · 2021-08 · Computer Science Stack Exchange · on “is Turing machine the blue print for program (software) or computer (hardware)?”
At no point of execution does a Turing machine need infinite storage, so you do not need all of it ahead of time. And it is quite possible to create physical models of a Turing machine [this video] . It is largely *irrelevant* that they do not have "infinite" tape, and is certainly misleading to claim that they are "not real Turing machines" because of that. If Zuse or von Neumann held such an attitude, they would have given up on building modern computers even before they began.