Stuff You Should Know: The World's First Computer

[Friendly]

First electromechanical computer: Z3 (May 1941)
http://en.wikipedia.org/wiki/Z3_%28computer%29

* Frequency: 5.3 Hertz
* Average calculation Speed: Addition 0.8 seconds Multiplication 3 seconds
* Arithmetic Unit: Binary floating point, 22 bit, add, subtract, multiply, divide, square root
* Data memory: 64 words with a length of 22 bits
* Program memory: Punched celluloid tape
* Input: Decimal floating point numbers
* Output: Decimal floating point numbers
* Input and Output was facilitated by a terminal, that had a special keyboard and a row of lamps to show results[4]
* Elements: Around 2,000 relays (1,400 for the memory)[4]
* Power Consumption: Around 4000 watts
* Weight: Around 1,000 kilograms (2,200 lb)

First commercial digital computer: Z4 (1942-45)
http://en.wikipedia.org/wiki/Z4_%28computer%29

* Frequency: (about) 40 hertz
* Average calculation speed: 400 ms for an addition, 3 seconds for a multiplication. Approximately 1000 floating point arithmetic operations on average an hour.
* Programming: holes in 35mm film stock, punched on a programming machine
* Input: Decimal floating point numbers, punch tape
* Output: Decimal floating point numbers, punch tape or Mercedes typewriter
* Word length: 32 bits floating point
* Elements: (about) 2,500 relays, 21 step-wise relays
* Memory: Mechanical memory as for the Z1 (64 words, 32 bit)
* Power consumption: (about) 4 kW

Both constructed by Konrad Zuse (1910-1995)
http://en.wikipedia.org/wiki/Konrad_Zuse

[louisg]

This is really interesting stuff. Thanks for posting this!

Here's some more detail on the architecture, for you fellow CS dorks:
http://history-computer.com/ModernCompu ... /Zuse.html

[njiska]

What about Tommy Flowers and the Colossus? Everyone always remembers Bletchley Park for the work done by Alan Turing, but hardly anyone remembers that Flowers built the world's first electronic, digital, programmable computing device.

http://en.wikipedia.org/wiki/Colossus_computer

[rancor]

I've been wanting this book for ages:

The Apollo Guidance Computer: Architecture and Operation

Although it sounds like it would be kinda dry for the non-programming types (me).

Apparently an old monochrome 8-bit Gameboy has more power than the room-sized computers that sent the first men into space.

[Evilmaxwar]

Your wristwatch is probably more powerful too :p

[ED-057]

The World's First Computer

First electromechanical computer

So you are disqualifying the Analytical Engine for not being electrical? (or maybe 'cuz it was never finished...)

BTW, one time I had a dream where I was in a wooded area near the coastline of ancient Japan, and some dudes had built there a mechanical computer out of wood and rope which was forwards-compatible with the Sharp X68000.

[Friendly]

What about Tommy Flowers and the Colossus? Everyone always remembers Bletchley Park for the work done by Alan Turing, but hardly anyone remembers that Flowers built the world's first electronic, digital, programmable computing device.

http://en.wikipedia.org/wiki/Colossus_computer

Nope, Colossus was not the first computer by a long shot (it became operational in December 1943). Unlike Colossus, Z3 used digital floating point operations and was Turing complete (=general purpose). And while Z3 had data memory, Colossus had none. Z3 also had a way to store programs (extrernal tape), Colossus didn't. Remarkably, Z3 was even operated by a special keyboard (while Colossus was controlled by patch cables and switches). The reason why Z3 used electromechanic relays instead of electronic switches (which Zuse had wanted) was simply because funding for using vacuum tubes was denied- of course the difference would have been purely cosmetic, functionality would have been identical.

In short, Colossus lacked several key features commonly associated with computers, was sepcialized for only one task and became operational years after Z3. It wasn't the first electronic computational device either: "Zuse's coworker Helmut Schreyer built an electronic digital experimental model of a computer using 100 vacuum tubes in 1942, but it was lost at the end of the war."

[njiska]

Nope, Colossus was not the first computer by a long shot (it became operational in December 1943).

I didn't say it was the first computer, nor did I say it was turing-complete. I know full well that it's a specialized piece of equipment, but what is important is that it's the first completed electronic programmable computational device. Schreyer built a prototype that may have been first, but from what I can find there's minimal information on how well this prototype actually worked, if at all, and if it was programmable.

Look, I'm not trying to compete here. The Z3 and Z4 are both incredibly important to the history of computing. I'm just trying to share another piece of history that is far too often forgotten and is significant because it was developed independent of Zuse's work and while it remained a state secret for many years, still had an influence on the early British computer scene. Many of the parties involved in the original project would continue to work in the field after the war.

And thanks for bringing this whole topic up. I haven't had this much desire to re-read my computer history books in a long time and it's been great. The entire evolution of the machine is fascinating.

[Friendly]

Konrad Zuse's Z3 is still largely unknown in the English-speaking world, where for a long time ENIAC (and Colossus) were incorrectly considered to be the world's first computers.
For one simple reason: Zuse's computers were built in Germany. Zuse never really got the recognition he deserved, especially internationally. It's slowly changing now (70 years later) thanks to the free flow of information the internet provides. Until a few years ago the English Wikipedia entry for Z3 contained very little information, and it's still rather limited. A while ago I saw a BBC documentary on the history of computers from ~10 years ago, and it didn't even mention Zuse.

By the way, Zuse also created the first high level programming language (between 1943 and 1945):
http://en.wikipedia.org/wiki/Plankalk%C3%BCl

[louisg]

Konrad Zuse's Z3 is still largely unknown in the English-speaking world

Yeah, you don't hear a lot about it. I did learn a little about his programming language, Plankalk, during a language design class though.

[Mortificator]

There are several important machines on the spectrum between "definitely not a computer" and "definitely a computer." I don't think one can be unquestionably be singled out as THE first computer.