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Crash Course Computer Science Preview02m

Starting February 22nd, Carrie Anne Philbin will be hosting Crash Course Computer Science! In this series, we're going to trace the origins of our modern computers, take a closer look at the ideas that gave us our current hardware and software, discuss how and why our smart devices just keep getting smarter, and even look towards the future! Computers fill a crucial role in the function of our society, and it's our hope that over the course of this series you will gain a better understanding of how far computers have taken us and how far they may carry us into the future.

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Want to know more about Carrie Anne?
https://about.me/carrieannephilbin

Want more Crash Course in person? We'll be at NerdCon: Nerdfighteria in Boston on February 25th and 26th! For more information, go to http://www.nerdconnerdfighteria.com/

The Latest from PBS Digital Studios: https://www.youtube.com/playlist?list=PL1mtdjD

Early Computing: Crash Course Computer Science #111m

Hello, world! Welcome to Crash Course Computer Science! So today, we’re going to take a look at computing’s origins, because even though our digital computers are relatively new, the need for computation is not. Since the start of civilization itself, humans have had an increasing need for special devices to help manage laborious tasks, and as the scale of society continued to grow, these computational devices began to play a crucial role in amplifying our mental abilities. From the abacus and astrolabe to the difference engine and tabulating machine, we’ve come a long way to satisfying this increasing need, and in the process completely transformed commerce, government, and daily life.

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Want to know more about Carrie Anne?
https://about.me/carrieannephilbin

Want more Crash Course in person? We'll be at NerdCon: Nerdfighteria in Boston on February 25th and 26th! For more information, go to http:

Electronic Computing: Crash Course Computer Science #210m

So we ended last episode at the start of the 20th century with special purpose computing devices such as Herman Hollerith’s tabulating machines. But as the scale of human civilization continued to grow as did the demand for more sophisticated and powerful devices. Soon these cabinet-sized electro-mechanical computers would grow into room-sized behemoths that were prone to errors. But is was these computers that would help usher in a new era of computation - electronic computing.

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

The Latest from PBS Digital Studios: https://www.youtube.com/playlist?list...

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Boolean Logic & Logic Gates: Crash Course Computer Science #310m

Today, Carrie Anne is going to take a look at how those transistors we talked about last episode can be used to perform complex actions. With the just two states, on and off, the flow of electricity can be used to perform a number of logical operations, which are guided by a branch of mathematics called Boolean Algebra. We’re going to focus on three fundamental operations - NOT, AND, and OR - and show how they were created in a series of really useful circuits. And its these simple electrical circuits that lay the groundwork for our much more complex machines.

*CORRECTION* AT 1:27 the graph says "Quinary System" but then the graph shows 10 possible states - which is actually decimal. Technically, there should be only 5 possible values there, but the overall concept is still the same.


Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

The Latest from PBS Digital Studios: https://www.youtube.com/playlist?list...

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Representing Numbers and Letters with Binary: Crash Course Computer Science #410m

Please take our PBS Digital Studios Survey! https://www.surveymonkey.com/r/pbsds2017

Today, we’re going to take a look at how computers use a stream of 1s and 0s to represent all of our data - from our text messages and photos to music and webpages. We’re going to focus on how these binary values are used to represent numbers and letters, and discuss how our need to perform operations on larger and more complex values brought us from our 8-bit video games to beautiful Instagram photos, and from unreadable garbled text in our emails to a universal language encoding scheme.


Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

The Latest from PBS Digital Studios: https://www.youtube.com/playlist?list...

We’ve got merch!
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Want to know more about Carrie Anne?
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How Computers Calculate - the ALU: Crash Course Computer Science #511m

Take the 2017 PBS Digital Studios Survey: http://surveymonkey.com/r/pbsds2017. Today we're going to talk about a fundamental part of all modern computers. The thing that basically everything else uses - the Arithmetic and Logic Unit (or the ALU). The ALU may not have to most exciting name, but it is the mathematical brain of a computer and is responsible for all the calculations your computer does! And it's actually not that complicated. So today we're going to use the binary and logic gates we learned in previous episodes to build one from scratch, and then we'll use our newly minted ALU when we construct the heart of a computer, the CPU, in episode 7.

*CORRECTION*

We got our wires crossed with the Intel 4004, which we discuss later. The 74181 was introduced by Texas Instruments in 1970 but appeared in technical manuals around 1969. The design of the 74181, like most of the 74xx/74xxx series, was an open design which was manufactured by many other companies - Fairchild was one such

Registers and RAM: Crash Course Computer Science #612m

Take the 2017 PBS Digital Studios Survey: http://surveymonkey.com/r/pbsds2017. Today we’re going to create memory! Using the basic logic gates we discussed in episode 3 we can build a circuit that stores a single bit of information, and then through some clever scaling (and of course many new levels of abstraction) we’ll show you how we can construct the modern random-access memory, or RAM, found in our computers today. RAM is the working memory of a computer. It holds the information that is being executed by the computer and as such is a crucial component for a computer to operate. Next week we’ll use this RAM, and the ALU we made last episode, to help us construct our CPU - the heart of a computer.

*CORRECTION*

In our 16x16 Latch Matrix graphic, we inadvertently left off the horizontal row access line above the top row of latches. As a result, the highlighted line for the row at address 12 should actually be one line higher.


Produced in collaboration with PBS Digital Studios

The Central Processing Unit (CPU): Crash Course Computer Science #711m

Take the 2017 PBS Digital Studios Survey: http://surveymonkey.com/r/pbsds2017. Today we’re going to build the ticking heart of every computer - the Central Processing Unit or CPU. The CPU’s job is to execute the programs we know and love - you know like GTA V, Slack... and Power Point. To make our CPU we’ll bring in our ALU and RAM we made in the previous two episodes and then with the help of Carrie Anne’s wonderful dictation (slowly) step through some clock cycles. WARNING: this is probably the most complicated episode in this series, we watched this a few times over ourselves, but don't worry at about .03Hz we think you can keep up.

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

The Latest from PBS Digital Studios: https://www.youtube.com/playlist?list=PL1mtdjDVOoOqJzeaJAV15Tq0tZ1vKj7ZV

We’ve got merch!
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Want to know more about Carrie Anne?
https://about.me/carrieannephilbin

Want to find

Instructions & Programs: Crash Course Computer Science #810m

Take the 2017 PBS Digital Studios Survey: http://surveymonkey.com/r/pbsds2017. Today we’re going to take our first baby steps from hardware into software! Using that CPU we built last episode we’re going to run some instructions and walk you through how a program operates on the machine level. We'll show you how different programs can be used to perform different tasks, and how software can unlock new capabilities that aren't built into the hardware. This episode, like the last is pretty complicated, but don’t worry - as we move forward into programming the idea of opcodes, addresses, and registers at this machine level will be abstracted away like many of the concepts in this series.

Want to know more about the Intel 4004? You can read the manual here! http://bitsavers.trailing-edge.com/pdf/intel/MCS4/MCS-4_Assembly_Language_Programming_Manual_Dec73.pdf

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

The Latest from PBS Digital Studios: ht

Advanced CPU Designs: Crash Course Computer Science #912m

So now that we’ve built and programmed our very own CPU, we’re going to take a step back and look at how CPU speeds have rapidly increased from just a few cycles per second to gigahertz! Some of that improvement, of course, has come from faster and more efficient transistors, but a number hardware designs have been implemented to boost performance. And you’ve probably heard or read about a lot of these - they’re the buzz words attached to just about every new CPU release - terms like instruction pipelining, cache, FLOPS, superscalar, branch prediction, multi-core processors, and even super computers! These designs are pretty complicated, but the fundamental concepts behind them are not. So bear with us as we introduce a lot of new terminology including what might just be the best computer science term of all time: the dirty bit. Let us explain.

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

The Latest from PBS Digital Studios: https://www.yo

Early Programming: Crash Course Computer Science #1009m

Since Joseph Marie Jacquard’s textile loom in 1801, there has been a demonstrated need to give our machines instructions. In the last few episodes, our instructions were already in our computer’s memory, but we need to talk about how they got there - this is the heart of programming. Today, we’re going to look at the history of programming and the innovations that brought us from punch cards and punch paper tape to plugboards and consoles of switches. These technologies will bring us to the mid 1970s and the start of home computing, but they had limitations, and what was really needed was an easier and more accessible way to write programs - programming languages. Which we’ll get to next week.

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Want to know more about Carrie Anne?
https://about.me/carrieannephilbin

Want more Crash Course in person? We'll be at NerdCon: Nerdfighteria in Boston on February 25th and 26th! For more information, go t

The First Programming Languages: Crash Course Computer Science #1111m

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So we ended last episode with programming at the hardware level with things like plugboards and huge panels of switches, but what was really needed was a more versatile way to program computers - software! For much of this series we’ve been talking about machine code, or the 1’s and 0’s our computers read to perform operations, but giving our computers instructions in 1’s and 0’s is incredibly inefficient, and a “higher-level” language was needed. This led to the development of assembly code and assemblers that allow us to use operands and mnemonics to more easily write programs, but assembly language is still tied to underlying hardware. So by 1952 Navy officer Grace Hopper had helped created the first high-level programming language A-0 and compiler to translate that code to our machines. This would eventually lead to IBM’s Fortran and then a g

Programming Basics: Statements & Functions: Crash Course Computer Science #1211m

Today, Carrie Anne is going to start our overview of the fundamental building blocks of programming languages. We’ll start by creating small programs for our very own video game to show how statements and functions work. We aren’t going to code in a specific language, but we’ll show you how conditional statements like IF and ELSE statements, WHILE loops, and FOR loops control the flow of programs in nearly all languages, and then we’ll finish by packaging up these instructions into functions that can be called by our game to perform more and more complex actions.

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Want to know more about Carrie Anne?
https://about.me/carrieannephilbin

The Latest from PBS Digital Studios: https://www.youtube.com/playlist?list=PL1mtdjDVOoOqJzeaJAV15Tq0tZ1vKj7ZV

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Facebook - https://www.facebook.com/YouTubeCrash...
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Tu

Intro to Algorithms: Crash Course Computer Science #1311m

Algorithms are the sets of steps necessary to complete computation - they are at the heart of what our devices actually do. And this isn’t a new concept. Since the development of math itself algorithms have been needed to help us complete tasks more efficiently, but today we’re going to take a look a couple modern computing problems like sorting and graph search, and show how we’ve made them more efficient so you can more easily find cheap airfare or map directions to Winterfell... or like a restaurant or something.

Ps. Have you had the chance to play the Grace Hopper game we made in episode 12. Check it out here! http://thoughtcafe.ca/hopper/

CORRECTION:
In the pseudocode for selection sort at 3:09, this line:
swap array items at index and smallest
should be:
swap array items at i and smallest

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Want to know more about Carrie Anne?
https://about.me/carrieannephilbin

The Latest from PBS Di

Data Structures: Crash Course Computer Science #1410m

Today we’re going to talk about on how we organize the data we use on our devices. You might remember last episode we walked through some sorting algorithms, but skipped over how the information actually got there in the first place! And it is this ability to store and access information in a structured and meaningful way that is crucial to programming. From strings, pointers, and nodes, to heaps, trees, and stacks get ready for an ARRAY of new terminology and concepts.

Ps. Have you had the chance to play the Grace Hopper game we made in episode 12. Check it out here! http://thoughtcafe.ca/hopper/

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Want to know more about Carrie Anne?
https://about.me/carrieannephilbin

The Latest from PBS Digital Studios: https://www.youtube.com/playlist?list=PL1mtdjDVOoOqJzeaJAV15Tq0tZ1vKj7ZV

Want to find Crash Course elsewhere on the internet?
Facebook - https://www.facebook.com/YouTubeCrash...
Twitter - h

Alan Turing: Crash Course Computer Science #1513m

Today we’re going to take a step back from programming and discuss the person who formulated many of the theoretical concepts that underlie modern computation - the father of computer science himself: Alan Turing. Now normally we try to avoid “Great Man" history in Crash Course because truthfully all milestones in humanity are much more complex than just an individual or through a single lens - but for Turing we are going to make an exception. From his theoretical Turing Machine and work on the Bombe to break Nazi Enigma codes during World War II, to his contributions in the field of Artificial Intelligence (before it was even called that), Alan Turing helped inspire the first generation of computer scientists - despite a life tragically cut short.

Special thanks to Contributing Writer Robert Xiao whom we should have (and forgot) to include in the credits. His help with this episode was invaluable.

Ps. Have you had the chance to play the Grace Hopper game we made in episode 12. Ch

Software Engineering: Crash Course Computer Science #1610m

Today, we’re going to talk about how HUGE programs with millions of lines of code like Microsoft Office are built. Programs like these are way too complicated for a single person, but instead require teams of programmers using the tools and best practices that form the discipline of Software Engineering. We'll talk about how large programs are typically broken up into into function units that are nested into objects known as Object Oriented Programming, as well as how programmers write and debug their code efficiently, document and share their code with others, and also how code repositories are used to allow programmers to make changes while mitigating risk.

Ps. Have you had the chance to play the Grace Hopper game we made in episode 12. Check it out here! http://thoughtcafe.ca/hopper/

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Want to know more about Carrie Anne?
https://about.me/carrieannephilbin

The Latest from PBS Digital Studios:

Integrated Circuits & Moore’s Law: Crash Course Computer Science #1713m

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So you may have heard of Moore's Law and while it isn't truly a law it has pretty closely estimated a trend we've seen in the advancement of computing technologies. Moore's Law states that we'll see approximately a 2x increase in transistors in the same space every two years, and while this may not be true for much longer, it has dictated the advancements we've seen since the introduction of transistors in the mid 1950s. So today we're going to talk about those improvements in hardware that made this possible - starting with the third generation of computing and integrated circuits (or ICs) and printed circuit boards (or PCBs). But as these technologies advanced a newer manufacturing process would bring us to the nanoscale manufacturing we have today - photolithography.

Check out Veritasium's video: How Does a Transistor Work?
https://www.youtub

Operating Systems: Crash Course Computer Science #1813m

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So as you may have noticed from last episode, computers keep getting faster and faster, and by the start of the 1950s they had gotten so fast that it often took longer to manually load programs via punch cards than to actually run them! The solution was the operating system (or OS), which is just a program with special privileges that allows it to run and manage other programs. So today, we’re going to trace the development of operating systems from the Multics and Atlas Supervisor to Unix and MS-DOS, and take at look at how these systems heavily influenced popular OSes like Linux, Windows, MacOS, and Android that we use today.

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

Want to know more about Carrie Anne?
https://about.me/carrieannephilbin

The Latest from PBS Digital Studios: https://www.youtube.com/playlist?list=PL1mtdjDVOoOqJzeaJAV15Tq0tZ1v

Memory & Storage: Crash Course Computer Science #1912m

Pre-order our limited edition Crash Course: Computer Science Floppy Disk Coasters here! https://store.dftba.com/products/computer-science-coasters
So we’ve talked about computer memory a couple times in this series, but what we haven’t talked about is storage. Data written to storage, like your hard drive, is a little different, because it will still be there even if the power goes out - this is known as non-volatile memory. Today we’re going to trace the history of these storage technologies from punch cards, delay line memory, core memory, magnetic tape, and magnetic drums, to floppy disks, hard disk drives, cds, and solid state drives. Initially, volatile memory, like RAM was much faster than these non-volatile storage memories, but that distinction is becoming less and less true today.

CORRECTION: AT 5:00 we say "around 9 kilobytes" when we should have said "kilobits".

Produced in collaboration with PBS Digital Studios: http://youtube.com/pbsdigitalstudios

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