How to save 51 billion lives for 68 cents with simple Engineering

Using the power of engineering and brilliant inventions to save lives!!! Great times collab-ing with Bill and Melinda Gates! You should check out the Gates Annual Letter here:
Pre-order a paper microscope here-
Read the published paper on the paper centrifuge, its cool-

0:15- The Ocean- Andrew Applepie-
2:18- Sweet Tomorrow- Andrew Applepie-
4:21- Berlin- Andrew Applepie-
7:54- Special song written just for me- Lincoln Hoppe,

Summary: I met with Manu Prakash from Stanford to talk about 2 of his labs' inventions the Foldscope and the Paperfuge. Combined these cost only 68 cents and they can be used to diagnose Malaria. Both of these are examples not only of simple, brilliant design, but of how engineering is used to make a positive dent in the world.

I make videos like this once a month all year long while supplies last:
TWITTER: #!/MarkRober
INSTAGRAM: markrober


  1. JakeyGodlyAwsome

    JakeyGodlyAwsomePrije 5 sati

    Total population 8 billion Title: 51 billion

  2. Nugget is Nugget

    Nugget is NuggetPrije 7 sati

    Disliked. Maybe a blood warning next time?

  3. ariyan sinha

    ariyan sinhaPrije 7 sati


  4. Nonexistent Cheese

    Nonexistent CheesePrije 8 sati

    comeon 1 more penny please

  5. EAZG yt

    EAZG ytPrije 9 sati

    Not even 51b people in this world

  6. Leo Drpić

    Leo DrpićPrije 9 sati

    I like the microbial roomba

  7. I like Cats

    I like CatsPrije 10 sati

    How can you save 51 billion lives when there are only 7 billion people edit: ohhhhhh it's because 51b people have died from it

  8. anestis Politis

    anestis PolitisPrije 11 sati

    But the world has only 7 billion lives..

  9. Franz S

    Franz SPrije 13 sati

    This is very inspiring and impressive. Great job

  10. TheHellLord

    TheHellLordPrije 13 sati

    51 billion? seems legit

  11. bob memer

    bob memerPrije 13 sati

    Imagine having the suppose of the 2nd richest man alive

  12. KellyMarie St.Bernard

    KellyMarie St.BernardPrije 13 sati

    I didn't know that flies could sese ur hand before it comes I just thought they were super ultra super fast😭😭😭😭

  13. Kaivaly Daga

    Kaivaly DagaPrije 15 sati

    But there are only 7 billion people

  14. grayboi duck

    grayboi duckPrije 17 sati

    I have a question when you know you have malaria then what do you do

  15. Jordan Lin

    Jordan LinPrije 18 sati

    Everybody be popping their pimples to get a sample of their blood.

  16. Lucy Connelly

    Lucy ConnellyPrije 18 sati

    Mark is super smart and most people would be cocky about that when mark uses his intelligence to do amazing things

  17. TheHiddenCode

    TheHiddenCodePrije 19 sati

    The guy is so humble that every time he is asked a question he answers like a kid.

  18. Mr Manga

    Mr MangaPrije 19 sati

    I was assembling the microscope and centrifuge when I then got a paper cut that dropped some blood onto the centrifuge, I then used the microscope and found out I have malaria

  19. Eliza Cakla

    Eliza CaklaPrije 19 sati

    Totes adorbs 🤣🤣🤣🤣

  20. Wolf King

    Wolf KingPrije 20 sati

    In the title it says saving 51 billion lives even though there's only 7.8 billion people on the planet

  21. JTM02 11

    JTM02 11Prije 21 sat

    Wait theres only 7 billion people one earth

  22. I dunno

    I dunnoPrije 21 sat

    how is he saving 51 billion people when theres only 7 billion pepole in the world rn

  23. Pierantonio Durante

    Pierantonio DurantePrije 21 sat

    Vorrei tanto ascoltare le motivazioni per quei 5973 non mi piace - I would like to listen to the reasons for those 5973 "i don't like" I think was 5973 heartless.

  24. Ciara Oldham

    Ciara OldhamPrije 23 sati

    Who the heck would dislike

  25. victor 91

    victor 91Prije 23 sati

    Are these still being used or some big corporations patented now goes for 100 bucks

  26. Kevin Skywalker

    Kevin SkywalkerPrije dan

    Scientists: imma pretend I didn’t hear him

  27. Missy Beak

    Missy BeakPrije dan

    Microbial r o o m b a

  28. Mr Freak Freaking

    Mr Freak FreakingPrije dan

    The one for examining blood still costs like a huge price.

  29. Alex Fang

    Alex FangPrije dan

    This is going to help a lot of people!!!!!!!!!!

  30. Jakub Macura

    Jakub MacuraPrije dan

    Make it a cent more expensive

  31. Hey That Brother

    Hey That BrotherPrije dan


  32. Lu SorExe

    Lu SorExePrije dan

    Who the heck would give this a dislike

  33. Jerry Hi

    Jerry HiPrije dan

    Title how to save 51 billion people for 68 cents Me there’s only 7 billion people on earth 🌍

  34. EZ Gaming

    EZ GamingPrije dan

    Title: save 51 billion people But there’s only 7.6 billion people on earth..... Edit: I don’t think anyone wrote this comment did they? Because I didn’t see anyone post it.

  35. Jeffrey Chen

    Jeffrey ChenPrije dan

    at <a href="#" class="seekto" data-time="253">4:13</a>, did anyone notice some strange creature near the pond moving its "head" around?

  36. Akash pruthi

    Akash pruthiPrije dan

    It looked like a penus at first glance

  37. Coma Craft

    Coma CraftPrije dan

    Oh 51 billion lives I am the 51,000,000,001 oof to me

  38. vansh patel

    vansh patelPrije dan

    lets hope manu does something for covid 👍

  39. ___ DaDoo ___

    ___ DaDoo ___Prije dan

    Covid can be solved with this work!

  40. Ishraj singh

    Ishraj singhPrije dan


  41. Saurabh Parmar

    Saurabh ParmarPrije dan

    MIND = BLOWN! 🤯

  42. Kai Basil

    Kai BasilPrije dan

    We can save more lives if we stop masturbating.

  43. Lewis McGregor

    Lewis McGregorPrije dan

    represent from india lets go

  44. Amit Charan

    Amit CharanPrije dan


  45. Frank Nederhand

    Frank NederhandPrije dan

    How could you dislike this video? What is wrong with these people! This is such a break through. I can imagine taking this to an ER and wowing the staff. It's just that amazing

  46. BlaD3xDragon

    BlaD3xDragonPrije dan

    mark rober is the best teacher ever

  47. didz

    didzPrije dan


  48. Octavio Samayoa

    Octavio SamayoaPrije dan

    why did so many people dislike it just makes no sense

  49. adhirajsaxena

    adhirajsaxenaPrije dan

    Mark! I love you man... Can't blv I discovered ur channel like few weeks ago. Stay safe and keep creating

  50. Luis Gabriel Cuervo

    Luis Gabriel CuervoPrije dan

    What an excellent video and innovations, well done!

  51. Aayush M

    Aayush MPrije dan

    The earth population is 7 billion

  52. dQw4w9WgXcQ

    dQw4w9WgXcQPrije dan

    100 billion people have lived on earth since the first human was born

  53. Joe Mama

    Joe MamaPrije dan

    I think they mean million and not billion

  54. Brandon Albers

    Brandon AlbersPrije dan

    No he means billion. There is currently 7 billion people on earth, he is talking about over thousands of years. Because malaria isn’t new and has been killing humans for generations.

  55. Brawl Stars Clips

    Brawl Stars ClipsPrije dan

    Carefully, He’s A Hero

  56. EGO IDK

    EGO IDKPrije 2 dana

    51 billion lives?

  57. Snow Flake

    Snow FlakePrije 2 dana

    Let’s be real poor people are on this earth because everyone can’t be rich otherwise if everyone is rich no one is actually rich ur all the same. All lives could be saved but they are not for this reason.

  58. dQw4w9WgXcQ

    dQw4w9WgXcQPrije dan

    everyone can have a stable income. not be rich but have a stable income to support their family.

  59. Sophia Marian

    Sophia MarianPrije 2 dana

    That mosquito has a really weird shaped mouth.

  60. Y0boY1342

    Y0boY1342Prije 2 dana

    He did not say consider subscribe

  61. maps 3377

    maps 3377Prije 2 dana

    Simply amazing.

  62. Calvin Ma

    Calvin MaPrije 2 dana

    Saving 43billion non existent lives :D

  63. dQw4w9WgXcQ

    dQw4w9WgXcQPrije dan

    and 7 billion existing lives

  64. Tyler Chubb

    Tyler ChubbPrije 2 dana

    Suprisingly I haven't seen a conspirator mention the bill and Malinda Gates foundation 👍🤣🤣🤣

  65. Anna Luksha

    Anna LukshaPrije 2 dana

    For the love of all that is good and right and true, don't say centrifugal force, no one in the video did but just don't please it's painful and I'm not even super sciencey

  66. SQW0

    SQW0Prije dan

    Care to elaborate? Mark did say centrifugal at 4:55. Are you saying he's wrong?

  67. Roland Slezas

    Roland SlezasPrije 2 dana

    Sees bacteria Mark Rober: Hey look, a microbial roomba

  68. J Y

    J YPrije 2 dana

    Wolbachia disliked this video.

  69. Robert Kamminga

    Robert KammingaPrije 2 dana

    <a href="#" class="seekto" data-time="102">1:42</a> WHYYYYY IS THIS NOT ON PHONES?!?!?!?!?!!?!?!

  70. dQw4w9WgXcQ

    dQw4w9WgXcQPrije dan

    because you're phone can't spin at a few thousand rmp and can't zoom that much

  71. xXdried_potatoXx

    xXdried_potatoXxPrije 2 dana


  72. out of order

    out of orderPrije 2 dana

    I’m pretty sure there’s only 7 billion people on earth

  73. dQw4w9WgXcQ

    dQw4w9WgXcQPrije dan

    since the first human was born there is an estimated figure that says that 100 billion people have lived on earth and half of them have dies from malaria.

  74. Jonathan Cook

    Jonathan CookPrije 2 dana

    Everyone that's ever been born

  75. Woof Woof

    Woof WoofPrije 2 dana

    They were 1 cent away

  76. Area51Alien 1234

    Area51Alien 1234Prije 2 dana

    I wonder what the results where and why Mark didn’t show them unless... Mark has Malaria

  77. Dissmo

    DissmoPrije 2 dana

    Only plasmodia disliked this

  78. Wyatt Lee

    Wyatt LeePrije 2 dana

    How can you save 51 billion lives

  79. ii_kb

    ii_kbPrije 2 dana

    But there is only 7 billion people on the earth

  80. Star

    StarPrije 2 dana

    He means everyone yhat has ever been born

  81. destiny phongmany

    destiny phongmanyPrije 2 dana

    Says ‘umbrella’ for one second during lab talk. 🙄

  82. Danté Lucassen

    Danté LucassenPrije 3 dana

    not t be rude but, there is not 51 billion people on Earth...

  83. Star

    StarPrije 2 dana

    It means everyone that has ever been born

  84. kipsu 75

    kipsu 75Prije 3 dana


  85. Myles Madill

    Myles MadillPrije 3 dana

    I’m <a href="#" class="seekto" data-time="322">5:22</a>

  86. AKASH CP

    AKASH CPPrije 3 dana

    Ivdem malayali undo?

  87. The Pixelator

    The PixelatorPrije 3 dana

    Wait.... I thought there was 7bil people in the world

  88. dQw4w9WgXcQ

    dQw4w9WgXcQPrije dan

    the sum of every single person that has ever lived is estimated to be around 100 million and half of them have died from malaria.

  89. Lolomanolo57

    Lolomanolo57Prije 2 dana

    There is about so :)

  90. Cal6009

    Cal6009Prije 3 dana

    He's also incredibly humble.

  91. Moonyzz

    MoonyzzPrije 3 dana

    earth: *has 8 billion people* mark rober : *how to save 51 billion people*

  92. MJK midnight

    MJK midnightPrije 3 dana