Computer Scientist Answers Computer Questions From Twitter

Hello world, my name is Professor David J. Malen, I teach

computer

science at Harvard, and I'm here today to answer your

questions

from Twitter. This is

computer

science support first from Tad Proletarian. How do search engines work so fast? The short answer really is. Distributed computing, i.e. Google, Bing and other similar search engines don't have just one server and they don't even have a really big server, they have hundreds of thousands, probably hundreds of thousands or more servers today all over the world. world. world, so when you and I go into O2 Google or Bing and maybe type in a search word like cat, it's quite possible that when you hit Enter and that keyword like cats is sent over the Internet to Google or Bing, It actually spreads. ultimately across multiple servers, some of which get the first 10 results, some of which get the next 10 results, the next 10 results so you can see just one collection of results, but a lot of those ideas come from of many of those search results. different places and this eliminates what could be a bit of a bottleneck if all the information you need had to come from a specific server that could very well be busy when you have that question Nick asks: will computer programming jobs be assumed by AI?

In the next five to ten years, this is going to be a very common question today and I don't think the answer is yes, and I think we've already seen evidence of this from the beginning, when people were creating websites, they were literally writing. generated code in a language called HTML by hand, but then of course software came out along with tools like Dreamweaver that you could download to your own computer that would generate some of that same code more recently, although now you can just sign up to websites like Squarespace. and Wix and others whereby you click, click, click and the website will be generated for you, so I dare say that certainly in some domains AI is actually just an evolution of that Trend and it has not stopped to out-of-work humans as much as you.

And I think my AI is much more productive and the ability to suddenly be able to program with natural language will enhance what you and I can already do logically but much more mechanically and I think it's also worth considering that there are so many bugs. or bugs in software in the world and there are so many features that humans wish existed in present and future products that it is a to-do list, so to speak, that is much longer than we will ever have time to finish in our lives. , so I think the prospect of having artificial intelligence that increases our productivity and works alongside us, so to speak, as we try to solve problems will simply mean that you, I and the world together can solve many more problems and move forward together. an even faster pace.

Next, Sophia, who asks how microchips work. It's just a piece of green metal. Well, here, for example, we have a bunch of microchips on what is called a logic board or sometimes known as a motherboard. There are many ports that may look familiar to you. with, for example, here are some ports for audio, here are some ports for networking, here are some ports for USB and some other devices as well and those ports, meanwhile, are connected to many different chips on this board that know how to interpret the signals from those ports and perhaps the largest chip on this motherboard tends to be something called the CPU or central processing unit, which is actually the brain of the computer and what you can't necessarily see because most of it is on reality paint and no traces. but if I turn this around, you'll actually see in the right light and at the right angle a bunch of traces running up, from left to right on this logic board that connects all these microchips and by Trace I mean a little bit wire that has been etched into the top or bottom of this circuit board that connects two parts of it now, what could these microchips be doing right?

They could just be interpreting signals coming from these two ports, they could be performing math doing something. with those signals to convert input to output or they could just be storing information, ultimately in fact there are different types of memory on a logic board like this, whether it's Ram or ROM or similar, so some of those chips They could well be storing information while the computer is plugged in or, in some cases, depending on the device, even when the power goes off. Alright, next a question from nkhe, so if someone can learn to code, what do computer

scientist

s do for four years in college, usually in an undergraduate program in computer science or computer engineering or a similar field? , someone spends a lot more time learning about the field itself than about programming specifically, so you can study not just a little bit of programming but also mathematics, certain fundamentals that transcend the particular classes you may have taken in middle school or secondary, but can be used to solve important or real-world problems.

You might learn something about networking. How you can send information from point A to point B. You might learn about graphs. How you can show things on the screen. or even create interactive animations or the like, you can learn how to leverage certain ideas from mathematics and other fields to implement your own artificial intelligence today, whereby you use probability, statistics, and information in general to try to predict what If you are an intelligent individual or in this case the computer might say in response to a question, then the computer is science in itself, it is a very broad field and programming is really just a tool that you tend to learn along the way.

Maya Shelby, how do you convert zeros and ones on the Internet? Well, I think the simplest answer is that the Internet is based on layers and layers and layers of ideas and if we start at the lowest of those levels, zeros and ones, we have something called binary, where zeros and ones can also be use to represent any other number. if we use more and more zeros and ones, more and more binary digits or bits, so to speak, we can count more and more and more and then if you and I agree, okay, let's not just use these patterns of zeros and ones to represent numbers, what if we reserve some of these patterns to represent letters like the English alphabet and then maybe you and I can decide to reserve certain patterns of zeros and ones to represent colors like red, green and blue in combinations of the Once we have the ability to represent colors, then we could represent entire images because what is an image on your phone or on a computer screen, is actually just a grid of dots, each of which has its own color, so all of this is to say that even if we start with this The lowest level of just zeroes and ones, as long as you and I and all the devices we use agree to follow some standard like this, we can build these layers and layers of abstraction, so to speak, one on top of the other until finally you and I arrive. above with a pattern of zeros and ones that represents sending this information of mine there and so we have something like Internet Majin Buu asks, can someone who knows computer science explain to me why computers use binary and not trinary encoding when it is trinary? is supposed to be faster, so it is not necessarily the case that a trinary system that would use three symbols, for example zero one and two, is necessarily faster than binary because the binary system that uses only zero and one tends to be simpler to implement and also more robust from potential errors or if you are familiar with voltage levels like in a battery, it is very easy for a computer to distinguish something like zero volts or three volts, but it becomes a little more difficult if we try draw the line somewhere in the middle because there's just a higher chance that a computer can mistake a voltage level like 1.5 in the middle is maybe being a little bit closer to off than on or on than off this is also where although there could be mathematical efficiencies in the real world, efficiencies in using trinary otherwise known as ternary as a zero, one and two digits instead of just zeros and ones, it turns out that today our world runs on electricity and there is so much momentum behind the binary which tends to be a net positive result.

Rachel Q95 asks why every Windows Solution, have you tried restarting and why does that always work? It's a very harsh fix for what are usually just bugs or bugs in software, for example Windows. In this case, restarting a computer simply starts everything from scratch, so all computers fall short. -Term memory is lost and everything starts in perfect condition, that is, it starts exactly the way Microsoft's programmers intended without the computer's potential distractions being in some strange state or condition that the programmers simply did not anticipate . maybe you clicked some buttons in a strange order maybe you opened a strange file but maybe you put the computer in a state that just wasn't programmed correctly Jason Whitmer is now asking what the best operating system is, well this is one of these

questions

In Computing we would call it a religious question, since it evokes a religious debate about which might be the best, of course, between the most popular operating systems that exist: Windows and Mac OS, but there is also one that you may not have heard of and it's called Linux. is actually very ubiquitous in the business world, which is why many of today's servers run Linux, so many of today's desktop or laptop computers run Windows or Mac OS, that doesn't mean you can't run all of those operating systems in different contexts and some of us actually run Linux on our own computers, so a lot of this comes down to personal preference.

I wouldn't even say there is a best operating system, but there tend to be correlations between the operating systems people use and the applications they have. Note that Windows, for example, is very popular in the world of PCS and desktop and laptop computers. Mac OS is, to some extent, particularly in academia in certain countries, but not necessarily on the same scale. Linux, on the other hand, is again used heavily on the server. industry side, but so is Windows, so a lot of the choices for operating systems sometimes come from what's most appropriate, what's most popular, what's most supportive, but some also comes from just the personal preference of the engineer, perhaps the first engineer you hire. make one of those decisions so that it's more about what's best for you and not so much about what's best overall.

Next Julio Magnífico asks why computers aren't getting cheaper. Well, computers or at least the internal parts of computers tend to be cheaper. It's that your expectations and my expectations keep rising, we want our phones, our laptops, our desktops to do more and more in the way the software runs the games we play and how quickly they perform for us, so even though some of those parts are becoming less expensive and I want them to make more and more and be faster and in greater quantity and as a result, I daresay the price is not going down as much as you might expect, That being said, today it is possible.

For the same amount of money as yesteryear you get much more in terms of computing power, so you could say that it is working to our benefit in some cases. Next, Darrow Nabila, can someone explain cloud computing to me like a five-year cloud computing? Basically, you are using someone else's servers that someone is paying to rent, for example, or timeshare, so this is not really a new idea or a new technology, but rather it is a better brand of a technique that has been used for years not only in the computing world but also in the real world as well, where someone like Google or Microsoft or Apple or others today could afford many, many servers and then make those servers available to me in part for you and many other clients too.

Marcus, hey, Marcus, well, Marcus is asking how computer memory works. He thinks that computer memory is actually driven by a bunch of switches that can be turned on and off. For example, if I take this light switch that is currently off, I could just say that this switch here represents the number zero in binary, but if I turn the switch right now I can say that I am representing the number one, of course, I can just count up to 0 to 1 with aonly light switch. but what happens if I bring a second light switch like this? If we start from scratch like this, we first turn on this switch and claim that it is one.

Let me now be more creative and turn this one off and turn this one on and now claim. This is how a computer memory could represent the number two and now if I turn this switch back on, I'll get a fourth pattern. This is how the number three could represent now, of course, if we add more and more of these switches. of these light bulbs we can count even more than three and, in fact, that is what a computer's memory ultimately does: use many, many small switches, also known as transistors, to turn the flow of electricity on and off and then it has others Types of hardware called, for example, capacitors that have the ability to retain some of that electricity, just like the light bulb that is lit below.

Donnie asks how do you explain web 3 to people, so that web 3 likes web 2 and, in retrospect, web one or just buzzwords that describe sort of phases of the Internet or the World Wide Web? as you and I know it, for example, at the time when only the World Wide Web existed, now perhaps called the web version. An information was largely static if it were creating a website on the Internet, you would write your code, you would write your content, you would put it on a server somewhere and someone could read that information, but were you the web developer or the website owner who was creating that content for other people to read and consume?

In Web 2, the world has become much more dynamic in recent years, so now websites tend to have databases and are more sophisticated, so much of the content on today's websites actually It comes from me and you, so if you think about any social media site, it's not the owners of those sites that create most of the content, it's you and me as users of those sites. websites, but on web 2, everything is very centralized, whether you're Twitter or Facebook, now meta or other companies, all that data, even in the social media world, comes from me and you, actually are stored centrally on those companies' servers, so web 3.0 or web 3, if you will, is really about potentially transitioning from that very centralized model to one that's more distributed where the data that you and I are creating and the data that you and I consume is actually distributed across multiple servers through a technique called blockchain, for example, in some cases where there is not necessarily one owner of that data, but really collective ownership and So verification that the data maybe comes from me and you, the next question is from Gomo Tigers.

Can someone explain to me the difference between firmware and software? Hardware is physical software is WTF code is firmware firmware is actually a synonym for a type of software, so firmware is just software, but it tends to be software that comes built into your hardware and you can think of, in the simplest scenario , that firmware is software that is just completely integrated into the hardware and itself cannot be changed or updated, but that's an oversimplification because even firmware, usually when it comes on a computer, when it comes on a phone or some other device, very often it can be updated, why?

It is the software that is actually closest to the hardware and in that sense it could well be the most important and if something goes wrong with The Firm, you may not even be able to turn on that device, whether it is a phone, a computer or even your refrigerator today, well that's all the questions for today, we hope you learned something along the way, see you next time.