“- Professor Brailsford: I checked this out weeks ago for a bit of light reading. - Ron Weasley: This is light?”

@@ikrotzkyhahah you got me bro

*International

BertyFromDK He is the embodiment of the history of digital computers. I can listen to him talk for hours.

TheTwick I completely agree. I wish i had had the opportunity to study under his guidance.

Get this man on WFPB diet so we can have him around longer. :)

Then declare it

Yes indeed. Some computer hardware used 9 bits to refer a byte. Telecoms engineers began to use the word octet to mean exactly 8 bits.

Hello, I am currently studying for my bachelors in electrical engineer and I'd like to chat with you about your career if that's okay?

I mean the way he mentioned it in the video I wouldn't have assumed 8 bits was always called a byte.

He literally had a section where he talked about how 8bits weren't always a byte. 8:22

True !

I can only agree. It's always a pleasure to watch him talk - even if some of it flies right over ones head (-;

What an odd comment. I wasn't aware that I was pretending otherwise.

LindaLooUK same.

LindaLooUK his passion yes. Lol.

It is a special skill he has when even those who understand little of what he says will nonetheless pluck up and listen, I wish all educators were the same.

So by your logic, 8 bytes (32 bits) would be a "feast"? Extending further would 16 bytes be a buffet? How many bits is a "take out"?

For computer speak, it's spelled "nybble."

2 bytes is a brownie

And if you lose a byte it could be a burp, losing 2 could be a hiccup, 4 a belch and 8 a puke, 16 a stomach pump and 32 DOA. Just continuing the food theme on a negative scale.

Cut a byte in half and it's a nybble; so . . . Cut a word in half and call those 2 bytes, a syllable. Fred

*quyte

I see what you did there. ;)

Alexander Robohm - If a byte is 8 binary digits, then would a quyte be 8 quaternary digits?

A qubit?

Roxor128 A quit?

Surely that would have been a bysex?

And "Cool"

He has a way of making everything sound exciting and interesting, too. I could watch him lecture about paint drying.

+Ronstar308 There would probably be some quite interesting physics involved if we got to the details. But that's not computer science...

alot of experience.

You all want to know the secret of representing space with a byte? Well, take a 2x2x2 cube and each of the eight 1x1x1 cubes within has a distinct value, 1 or 0. The only problem is when you look at this space-byte from the corner, there is one hidden bit. Now connect this way of representing space to a self driving car, and I claim you can represent the entire Universe with stacked space-bytes. Do any of you relate?

Well, depends if we just get the well-worn story of the PC itself (which is somewhat fascinating, given how much of a departure it was from IBM's usual operating procedure, but has been done to death elsewhere), with which IBM were relatively late to market and only managed really to steal a leading share on the strength of their name (and, I guess, how easy it was to shove a relatively large amount of memory into it, as well as the option of a very sharp terminal-like display), or if we get the backstory behind how they spent most of the 70s, basically from the arrival of the highly promising Intel 8008 / 8080 onwards, trying and failing to produce a "minicomputer in a shoebox" type system that would capture the small-and-home-office imagination in the same way that all their rivals (and, up to 1981, much more successful dominators) seemed to pull of even without thinking about it. They had a lot of interesting and diverse stabs at it with gradually more PC-like offerings, but for some reason it's only the PC itself that finally saw meaningful sales. If it had also flopped, it's likely IBM would have abandoned the small-system arena altogether and remained concentrated on massive corporate mainframes and the like instead. Which, though I'm not really a fan of the PC and XT themselves, still would have been a shame, because they built some fine machines in the late 80s and early 90s, especially when branching out into laptops, and after an early falter with the CGA and (in most applications) EGA, produced some excellent and cost effective display standards, rather earlier than you might have expected, in the VGA and XGA.

I would watch him talking to garlic bread flying to space for 2.5 hours.

I see what you did there...

Yes! This! So much this!

Interesting story. But ,for the Bendix machine and the Univac 1108 , were those bytes actually directly addressable ? Or was it just that 7 bits and 6 bits were the character widths?

They were the character widths, at least (the G-21 had a 127 or 128 character-set); as for addressability, I don't know. All we students were doing with either machine was programming it in ALGOL; we never dealt in assembly or any machine-code level addressing. It's certainly an interesting question. I kinda wish I knew how to find out. (BTW, this was at CMU in Pittsburgh. And I recall a researcher from the UK, Alan Bond, being there for a time, it would have been ca 1967-8, to develop a CRT-screen interface for the G-21. Pretty sure it was a vector-based graphics system. Any chance you might have known him? I don't know what university he was from in UK.) Fred

Wow, there was actually a computer with a 7-bit (well, 28-bit) architecture? How utterly bizarre. Were the G20s individually 14-bit, or did the conjoining work in a different way?

Turing proved that XOR gates could compute anything, but Babbage designed a universal calculator in the 19th century.

Which is why I'm edgy about seeking clarification over what I heard elsewhere that contradicts this account. The written record is one thing, but right from the mouth of someone who was actually _there_ somewhat trumps it. It'd just be nice to make sure which one is indeed right.

@@gwenynorisu6883 which part of it is contradicted?

Kyle Horne - on UKposts?! Are you mad? The comments will explode!

I once had the same software compiled on both a big and a little endian system. It used a binary format for configuration and outpuf files. What a horrible time that was.

Oh, yeah. That would be awesome. I bet the Professor has some snarky comments on that mess.

mipmipmipmipmip A file system I'm working on currently has both big *and* little endian files inside it...

Get Tom Scott in to rant about the headaches that go with it. It'll be up there with his ones about time zones and internationalisation.

actually, it's the key point of the rest of the video. what you're probably missing is that "word" refers to a specific amount of memory. for example, if a computer architecture has 32-bit registers, 32 bits is considered the word size of that computer. "word based" means that a word is the smallest amount of main memory that can be read from or written to. modern computers can usually address single bytes, allowing for a finer-grained memory access.

The word size is the natural integer and address size used by the CPU. Word based opposed to byte addressable relates to memory organisation. Both RISC & CISC computers prefer memory access aligned on natural sizes, every 4 bytes for int32 or 8 for int 64 for example. As register sizes and calculations can be done on even larger units eg) AVX 256 or 512, plus memory data access transfers occur in units of cache lines, the original concept of words became less useful. For example AMD64 cannot penalise use of 32bit integers over 64bit, as compatability with Win32 binaries was a key requirement.

Hahahaha

DecSystem20 (2060, actually a PDP-10) used 6-bit encoding for text, 36bit machine, 18-bit addressing. I learned a lot on that system, my first "big" machine after starting on Apple-II/TRS-80.

That’s where expressions like “two bits” for 25 US cents came from. Of course, the professor is British, so he wouldn’t mention that.

I was a hardware engineer at Digital from 1974 through 1982, and I worked in the PDP-11 systems engineering group. At CMU, where I got my degree, a PDP-8 was in the main EE lab on campus. So far as I know, it was the only computer on campus that undergraduates could actually touch -- as in start, stop, and toggle-in code (including the boot sequence). When I first got to Digital, there were four PDP-11 flavors -- each designed and built by a different designer. Digital created the VAX-11 as a 32-bit counterpart to the 16-bit PDP 11s. While I enjoyed this video, I have a different perspective on this history -- colored in no small part by my own history. It isn't that anything here is incorrect, it is instead that a lot was going on in the 1970s that isn't mentioned here. There is no mention of Digital, Prime, Data General, and so on. The first "personal computer" was the PDP-8 -- intentionally designed and built to be used by a single person. Digital arguably created the entire "low end" market by intentionally selling products where the price of each component was under $50K (some said $30K). This was not an arbitrary choice -- it was the threshold above which prospective customers had to capitalize the buy. The Digital business model was to bypass purchasing departments -- and therefore sidestep the dominance of IBM that this video talks about -- and instead sell directly to lab managers. I'm ignoring the "OEM play" that was the other big invention of Digital. In the early years of Digital, the PDP-8 had four 3-bit bytes per word while the PDP-11 had four 4-bit bytes per word. The PDP-11 was always byte-addressable. Finally, this video fails to mention another design choice of enormous import -- how are bytes indexed within a word? Is byte 0 the most significant or least significant byte? Anybody who's coded in C -- especially the C of the late 1970s -- is accustomed to worrying about "Endedness".

Funny, but true! Early computers were very expensive. You don't spend $10,000+ to do word processing...

Adam Feather IIRC it is the nearest power of 2 to 1000. 1000 in SI nomenclature is kilo, hence Kilo is used in computing parlance, with an upper case k to distinguish it from 1000. Likewise mega is used as the prefix to represent 10^6, the binary equivalent is 1024^2 again with an uppercase m. Coincidentally 1024 is 2^10.

Thanks for taking the time to reply. It feels like you're reiterating my intuitions on why ~1000 bytes was where the stick was put in the ground to signify the first quantity of bytes we consider of import: we're from a base10 world and already think in terms of thousands. 1000 just feels like an arbitrary number of bytes to put the the next label on from a purely base2 perspective.