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April 6, 2023 · 15 min read

Season 3, Ep. 20 – TWiTH: The IBM 360 Computer System, with Deividi Silva, VP of Technology at

How often would you replace your computer if the newest model wouldn’t work with your monitor, keyboard, or mouse? This is the core of the issue IBM was trying to solve when they developed the 360 System, as Faith and Deividi discuss in This Week in Tech History. It was a huge risk that ultimately paid off, and introduced the idea of interchangeable computer components to the world.


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Faith (00:05):

Hey, Deividi.

Deividi (00:06):

Hey, how’s it going?

Faith (00:07):

Good. How are you?

Deividi (00:08):

Doing great, yeah.

Faith (00:10):

I always forget that Thursdays are your “not at home” day.

Deividi (00:15):

I am today. I am at home. (Faith: Oh, you are?) I prepared for that. So the cleaning lady came up this morning. (Faith: Nice.) She cleaned all the apartments. So I have a clean place to talk to you,

Faith (00:28):

<Laugh>. I was gonna really judge you if you didn’t. (Deividi: <Laugh>.) So I’m glad that you prepared <laugh>. How’s your week going?

Deividi (00:36):

It’s going great, actually. I went to the Coldplay concert this Tuesday.

Faith (00:42):

Oh my gosh. How was it?

Deividi (00:44):

It was incredible, yeah.

Faith (00:46):

Ugh, I’ve heard that it feels like you’re on another planet. My friend went, and they released all these, kind of like, floating objects in the air, (Deividi: Yeah.) and it was just, it felt like zero gravity for a second.

Deividi (00:59):

It’s really incredible. It feels like you are in “paradise”, or like, to use the name of the song. (Faith: Yeah <laugh>.) or a different “universe”, again, to use another song. But it just, the whole experience with the bracelet, (Faith: Mm-hmm <affirmative>.) like, being on a full stadium, and the way that, especially Chris Martin, he treats people; he’s like a different kind of person. He’s like a special human being. So really, really, really great experience, overall.

Faith (01:38):

That’s so cool. You’re inspiring me. We’ve been debating about going to all the big tours that are happening this year, and I’m just such a homebody, you know? Like, once I’m there I’m like, this is so cool. And I live in Nashville, obviously, it’s Music City, there’s so much live music, but getting there, I’m always like, “Well, I could be in bed by 8:00,” and…<laugh>.

Deividi (02:01):

Oh my god, don’t do that. <Laugh>. Just the experience, you’re never gonna forget this, yeah.

Faith (02:06):

Right, exactly. Yeah, and once I’m there, I’m never sad that I’m not home in bed, right? (Deividi: Right <laugh>.) It’s just, thankfully I have like, a very fun, spontaneous, music-loving boyfriend.

Deividi (02:23):

Nice. He’s got you there.

Faith (02:25):

Yes. So I lean on him for that <laugh>. It keeps me fun. Obviously, you’ve been on the Frontier podcast before. These episodes are focused on a historic event. There is no pressure on you to be a historian or an expert on these topics <laugh>.

Deividi (02:44):

I thought you invited me, because I’m old, (Faith: <Laugh>.) and I might have used this thing. You looked at me and said, “Hey, this guy looks like he punched some cards.” <Laugh>.

Faith (02:56):

“Yeah, and was building computers in 1964.” No, that is not why, but I do think that this is like, a fun, kind of like, random historical fact that you’ll enjoy talking about with me. So that’s why you’re here.

Deividi (03:11):

Awesome. Yeah. Awesome.

Faith (03:14):

All right. Also, this historic event happened three days before my birthday, three days and many decades before my birthday, but…

Deividi (03:22):

Oh, you got me scared there for a moment. (Faith: Yeah <laugh>.) I thought, is she that old?

Faith (03:26):

You’re like, “Drop your skin care routine!” Yeah, no <laugh>. (Deividi: <Laugh>.) (RETRO SYNTHESIZER MUSIC PLAYS) On April 4th, 1964, IBM launched the System 360 mainframe and architecture. The system was made up of six models of computers that were compatible and interchangeable with 40 different peripherals. So it was dubbed the “360”, because it was designed to meet the needs of all types and sizes of customers with one unified software-compatible architecture. That’s a lot of words. Let’s figure out what that means. So up to this point, computer systems were not interchangeable, even if they did come from the same company. So that meant that new products rarely worked with old systems, which then meant that companies were reluctant to invest in upgrades, since they had already invested in the earlier version. So when IBM developed these new mainframes, they tackled that problem head-on by allowing future upgrades to be backwards compatible to all other 360 System mainframes. So at that time, it was considered one of the riskiest business gambles of all time. Wow. We’ve had a lot of riskier things than that happen since then, so that’s that’s interesting. It cost $5 billion to develop, which today would be a little over $45 billion.

Deividi (04:51):


Faith (04:52):

Yeah <laugh>. But it worked out in the end, thank god. In the first three months alone, IBM received $1.2 billion in orders, and within five years, they had sold over 33,000 units and popularized the concept of a computer upgrade. Thanks a lot, IBM. It was IBM’s most successful product launch ever, and by the mid ‘80s had generated over a hundred billion in revenue. That’s what I call a return on investment. Fun fact, the System 360 is also responsible for the worldwide standard of the 8-bit byte. (RETRO SYNTHESIZER MUSIC FADES OUT) Deividi, I’m wondering if you can explain the 8-bit byte standard to me like I’m five-years-old. Is that something that you know about?

Deividi (05:36):

You learned this in computer science, and up until this point, it wasn’t defined how the data would look like, right? You could have different types of data structures, and the 8-bit per byte means that you have eight bits in one byte, and that allows developers to know how they’re gonna manage their memory when they’re programming software, (Faith: Mmm <affirmative>.) and you can more easily allocate memory for your program. So it’s a nice way to define what is the standard, and everyone follows that after that. So it’s a great improvement, in terms of not having to rewrite everything in a different bit/byte (Faith: Mmm <affirmative>.) phase again. Like, if you are going to 6-bit/byte or 8-bit/byte, different things, you had to rewrite everything over and over again.

Faith (06:40):

So it sounds like this is just like a foundational building block of how we build software today.

Deividi (06:45):

Definitely, yeah.

Faith (06:46):

That’s cool. Obviously, in 2023, the way we think about updates is a lot different, and even still, I’m always reluctant to hit the “Yes, Update Now” button, because I’m like, you know, my whole life is on the internet, my whole life is on devices, and it’s just like, inconvenient for me to take a few minutes out of my day to click “Update”. So I’m just imagining, before this innovation from IBM, I mean, the friction to update just seems absolutely like, insurmountable, right? Like, and I think when you think about how frequent updates allow us to innovate, it seems impossible that we could have gotten to where we are today, in terms of like, rate of innovation without this, right? Without System 360.

Deividi (07:43):

Exactly, exactly. You define a standard architecture that allows programmers, and also hardware manufactures, to create things that they know it’s safe to do that, and you know it’s gonna work every time. So it’s a big change in the industry, you know, having different models run the same software. Before, you had to rewrite the software all over again. If you need a printer, guess what? You need a printer that works with that (Faith: Mm-hmm <affirmative>.) computer. Just, you need to recreate a printer or introduce the idea that you can insert more memory. So different use cases, different business, you could use more memory. So you have that memory card that you put in there to expand your IBM 360, and those are things like, you have your cell phone, you need more memory, you put more memory in there, but before that was, nothing like that existed. So it standardized all the architecture, the interfaces, as I said, so a third party could use the same thing and create their own product, so it creates a huge opportunity on the aftermarket. It set the ground for open standards. So the way that we think about creating software and collaboration and having, creating a platform where others can develop on top of that, it really sets the standards for that.

Faith (09:16):

Mmm <affirmative>. Yeah, I mean, I’m thinking, this is the example Abbey gave us, is like, you know, I’m sitting here today, I’ve got my aftermarket monitor in front of me, aftermarket keyboard and mouse, none of them are made from the same manufacturer, right? I’ve got my MacBook Air, that’s my machine, but my keyboard is a Microsoft keyboard. I’ve got a printer that’s HP, right? And I can’t imagine, I mean, if we put ourselves in the shoes of IBM in 1964, I can’t imagine that they were thinking too much about like, interoperability between IBM and other manufacturers, right? Like, it seems like they were really hamstrung on internal growth just with IBM products, and that’s kind of the impetus for the System 360. But it’s interesting, because I do think if we could get in a time machine and go back in time and be like, “Hey, you’re actually developing something that’s gonna allow, that’s gonna open up the competitive landscape pretty exponentially for you,” part of me thinks that they would still do it, because like you said, developing kind of on top of each other’s innovations just increases the rate at which we all win from those innovations, right?

Deividi (10:30):

Exactly. Those guys were true innovators, thinking that way. Imagine the pressure from the business, right? If you are a business that is striving, and you’re doing something, and you’re creating proprietary technology where (Faith: Mm-hmm <affirmative>.) you have your customer locked in to what you do, you see that the pressure from the business is “Do more of this. We need more people locked into our ecosystem,” but these guys, true innovators, thinking, “No, let’s open up. By opening up, you’ll see. We’ll create more opportunities for business.” And nowadays, everyone just follows that. You look at all companies, and everyone just took that idea from those times and just keeps doing that. Creating platforms work, and others can develop more things. It set the standard for the industry. Even things like the first protocols (Faith: Mm-hmm <affirmative>.) or networking, like Internet TCP/IP, they came from things from that time, from IBM 360. So it’s crazy to think about what one type of machine can do for the whole industry,

Faith (11:45):

Right. Yeah. I mean, you talk about risk, and, obviously, a $5 billion investment is like, <laugh> that’s crazy. You know, I can’t imagine having that kind of pressure to provide return on investment, but also without any sort of precedent for what you’re building, right? Like, I think of it like, I always use this example, but nobody really thought about how bad email sucked until we had Slack, and then it’s like, oh, of course there’s a different category for communication, but we don’t think that way until we have that alternative in front of us, and then the previous world seems like, kind of so silly. But I just, you know, I mean, and this is true for like, any kind of industry-shaping innovation, but it’s like, man to believe in a vision so much that you’re gonna invest $5 billion in it when the status quo is working. It could be better, but it’s working. IBM was still a company, they were creating products, people are buying the products. I wish that I had that kind of risk tolerance, ‘cause I think I would be a very wealthy woman <laugh>.

Deividi (12:57):

<Laugh>. If you think about it, like, different companies had that throughout the time. Some of them didn’t do it and just died. (Faith: Mm-hmm <affirmative>.) There’s a classic example with Kodak, with the films and photographs. They had that idea for creating digital cameras in-house. I think they, yeah, I think they had that, but no, the business is for selling films. (Faith: Yeah.) And it’s crazy to think about it, right? They let that go. Well, the company pretty much ended, and they were winning the whole market share. So it’s crazy to think about that. Sometimes you need to disrupt your own business to create new opportunities.

Faith (13:46):

Put that on a t-shirt. (Deividi: <Laugh>.) “Sometimes you have to disrupt your own business to create new opportunities.” That also hits close to home, Deividi, ‘cause I’m from basically the town where Kodak was based out of. (Deividi: Oh really?) Yeah. Rochester, New York. (Deividi: Cool.) But it, yeah, I mean, you’re totally right. It’s one of those things where we’re kind of giving conflicting stories, right? Like, one is stay in your lane, be a market leader, you know, just like, maintain your lead within that market, and along those lines of that same story, it’s like, well, you know, getting too broad is risky. (Deividi: Yeah.) But I think we’ve just seen again and again that, you know, the second road, which is “disrupt your own business”. Be the first. If you’ve got an idea, someone else is gonna have it soon, so, you know, you gotta be the first to market.

Deividi (14:39):

Definitely. Someone else is gonna do it. Yeah.

Faith (14:42):

Mm-hmm <affirmative>. Which is funny, because I mean, if you were to ask me, “Hey, Faith, what are the top three most innovative technology companies today?” I probably wouldn’t say “IBM,” but I am grateful for the foundations built by IBM. (Deividi: Yeah.) Especially, you know, System 360, as it turns out.

Deividi (15:02):

They do try. Back in, I don’t know, eight years ago, when I was living in Silicon Valley, IBM was, I think, at the time, really ahead of their time, talking a lot about IBM Watson and (Faith: Mm-hmm <affirmative>.) and AI innovation. But I think the routes that they took, like, I think that being at just such the way that they’re seeing as a corporation, and how they interact with other businesses, it feels like they don’t have the energy to go scrappy like a startup, (Faith: Mm-hmm <affirmative>.) and people see them that way, that they wanna collaborate with them. So people at the time said, “Yeah, that’s cool. That’s great. It’s great innovation, what you’re trying to do with AI here with IBM Watson.” Yeah. I’m not a big corporation; I’m not your customer, but it’s crazy to think about that.

Faith (15:58):

Right. You know, it also makes me think about, I mean, obviously, System 360 changed everything about the way we build software, and even how we monetize software. Like, imagine being hamstrung by adoption like that, still, where it was like, well, you know, we can develop <laugh> any number of programs, but like, nobody’s gonna buy ’em, because adoption is just so full of friction. But it kind of reminds me of the transition from Waterfall to Agile, right? Like it has that same kind of like, step-change (Deividi: Yeah, yeah.) effect, right? Like, and I’m curious about your thoughts. If we had to force rank those two, kind of, transitions and technical history, which do you think had the biggest impact on our rate of innovation as an industry?

Deividi (16:57):

I think, talking for myself, because of my career and where it led me to developing software as my thing, and I always think that if it hadn’t been this way, the iterative way, how you learn from customers and you iterate upon the new discoveries and do things again, and again, and again, and always making improvements along the process, I think I wouldn’t like my career very much if it wasn’t this way. So I think, selfishly, for me, I think this is the main thing. I love iterating, offering solutions, and talking to customers. So yeah. That’s how I see it.

Faith (17:47):

Yeah, and I guess, you know, hearing you talk about it, I think the two are actually like, we couldn’t have Agile without the environment that System 360 made room for. (Deividi: Yeah.) Shout out to whoever was on that team at IBM. We’re very thankful for you. We recognize your contributions <laugh>.

Deividi (18:10):

Thank you. My career would be very different without them. Yeah.

Faith (18:14):

Yes. This is also really good to know, because I feel like, for a lot of these historic events, I’m hesitant to ask people to be too much of an expert, but I feel like you actually were an expert here, so please expect another invite back to the Frontier podcast.

Deividi (18:31):

Oh, lemme talk about experts. I did a little research. (Faith: Oh!) Yeah. If we have any companies out there looking for developers who can program mainframes, I don’t know, maybe an IBM 360, if there’s one running out there that isn’t in a museum.

Faith (18:52):

No way <laugh>.

Deividi (18:52):

We have 26 developers on our platform with Fortran being one of their skills, which is a programming language that you can use with IBM 360. Twenty-three with COBOL.

Faith (19:09):

No way <laugh>.

Deividi (19:10):

Yes. And one person who’s, one of their top skills is assembly, very low level coding programming language. I talked to her, I interviewed her last year, and she is an amazing developer. She worked for Intel, looking for a job with us, approved in our platform. So if you are looking for someone that can talk directly to your computer with this crazy set of instructions, she’s here.

Faith (19:42):

That’s incredible. I wonder, it would be fun to do a “part 2” of this episode and have somebody, kind of, walk us through like, here’s what it actually looks like in practice. (THE FRONTIER THEME FADES IN)

Deividi (19:52):

Oh my god. I can try to get some punching cards and…<laugh>.

Faith (19:58):

<Laugh>. Great to know.

Deividi (19:59):

I don’t know how any of that works. I did have a teacher, a professor in college, that he worked with punching cards. Yeah, very, very nice. One of the best professors I’ve ever had. Shout out to Mr. Salvador.

Faith (20:14):

<Laugh>. Hey, Mr. Salvador. Thank you so much for your contributions. (Deividi: <Laugh>.) All right, Deividi, this has been awesome. I feel at least 10% smarter now, as usual, after talking to you, so…

Deividi (20:25):

Thank you very much. See you. Bye.

Faith (20:29):

Thanks for listening to The Frontier podcast, powered by We drop two episodes per week, so if you like this episode, be sure to subscribe on your platform of choice, and come hang out with us again next week, and bring all your internet friends. If you have questions or recommendations, just shoot us a Twitter DM @theFrontierPod, and we’ll see you next week. (THE FRONTIER THEME STOPS)