Crash Course Computer Science

Science and Nature Series / 1 Season

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!

Watch Latest: S1 E40

12m 21s

Files & File Systems: Crash Course Computer Science #20

S1 E20 / 11m 42s

Today we’re going to look at how our computers read and interpret computer files. We’ll talk about how some popular file formats like txt, wave, and bitmap are encoded and decoded giving us pretty pictures and lifelike recordings from just strings of 1’s and 0’s, and we’ll discuss how our computers are able to keep all this data organized and readily accessible to users. You’ll notice in this epis

Memory & Storage: Crash Course Computer Science #19

S1 E19 / 12m 17s

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,

Operating Systems: Crash Course Computer Science #18

S1 E18 / 12m 55s

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 goi

Integrated Circuits & Moore’s Law: Crash Course Computer Science #17

S1 E17 / 12m 29s

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 trans

Software Engineering: Crash Course Computer Science #16

S1 E16 / 10m 22s

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

Alan Turing: Crash Course Computer Science #15

S1 E15 / 12m 51s

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.

Data Structures: Crash Course Computer Science #14

S1 E14 / 10m 6s

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,

Intro to Algorithms: Crash Course Computer Science #13

S1 E13 / 11m 30s

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

Programming Basics: Statements & Functions: Crash Course Computer Science #12

S1 E12 / 11m 35s

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

The First Programming Languages: Crash Course Computer Science #11

S1 E11 / 10m 56s

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!

Early Programming: Crash Course Computer Science #10

S1 E10 / 9m 4s

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.

Advanced CPU Designs: Crash Course Computer Science #9

S1 E9 / 12m

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.

Instructions & Programs: Crash Course Computer Science #8

S1 E8 / 10m 14s

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

The Central Processing Unit (CPU): Crash Course Computer Sci #7

S1 E7 / 11m 15s

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 Car

Registers and RAM: Crash Course Computer Science #6

S1 E6 / 12m 7s

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

How Computers Calculate - the ALU: Crash Course Computer Science #5

S1 E5 / 11m 9s

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

Representing Numbers + Letters with Binary: Crash Course Computer Science #4

S1 E4 / 10m 38s

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.

Boolean Logic & Logic Gates: Crash Course Computer Science #3

S1 E3 / 10m 1s

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

Electronic Computing: Crash Course Computer Science #2

S1 E2 / 10m 43s

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

Early Computing: Crash Course Computer Science #1

S1 E1 / 11m 36s

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.

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