How does a blockchain work - Simply Explained

  • Опубликовано: 13 ноя 2017
  • What is a blockchain and how do they work? I'll explain why blockchains are so special in simple and plain English!

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Комментарии • 867

  • Robbie Culliton
    Robbie Culliton День назад

    Finally I understand blockchain ! Brilliant explanation thanks

  • mikey 0292
    mikey 0292 3 дня назад +1

    this vid sucks

  • Tien dien tu Viet
    Tien dien tu Viet 4 дня назад

    very simple, thanks

  • komal Roma
    komal Roma 4 дня назад

    very interestingly explained the whole process, cheers!

  • Mike Kleinsteuber
    Mike Kleinsteuber 5 дней назад

    Nicely described. It would have been nice to have added how 'Proof of Work' is accomplished.

  • Simon Xyz
    Simon Xyz 5 дней назад

    Thanks for the explanation!

  • PureHustler153
    PureHustler153 6 дней назад

    Would anyone agree that blockchain structure is similar to a linked list?

  • kellerr13
    kellerr13 6 дней назад

    Blockchain is nothing but CRC 2.0

  • bert boer
    bert boer 10 дней назад

    Thank you for this video, so much clearer than the others. Very nice.

    SHAM XHAM 10 дней назад

    Extraordinary project!!!!

  • Karan Krishnani
    Karan Krishnani 12 дней назад


  • Sarah Daniels
    Sarah Daniels 13 дней назад

    Would it be correct to say that blockchain is the way crypto currency works, not the crypto currency itself? It’s the process of moving and recording transactions?

    • Simply Explained - Savjee
      Simply Explained - Savjee  13 дней назад

      Yes, cryptocurrencies are built on top of a blockchain. A blockchain is just a tool that allows you to store data distributed and so that it can't be changed anymore.
      What data you store is unimportant. But cryptocurrencies obviously store transactions.

  • Neonexus
    Neonexus 14 дней назад

    I'm still not 100%, but this video has been the biggest help so far

  • Jake O
    Jake O 16 дней назад

    I finally get it. Well done. I have been trying to figure out what blockchain was for a very long time and nobody seemed to be able to explain it.

  • Se-Hyun Yang
    Se-Hyun Yang 16 дней назад

    sorry i dont get it why do you tamper hash? dont you want to tamper data?

    • Simply Explained - Savjee
      Simply Explained - Savjee  13 дней назад

      It's the inverse. In the video I tampered with the data and because the data was changed, the hash changes as well.

  • mymaninchampagne
    mymaninchampagne 17 дней назад

    At last, an understandable explanation of blockchain with clear, simple and yet informative illustrations and commentary. Thank you

    INFOCENTRO SUN-SUN 18 дней назад


  • palatable johnson
    palatable johnson 19 дней назад

    alot of people having all these questions and criticism
    if you would criticize fiat currency the same way, none of this would be necessary

    TECNO MUNDO 20 дней назад

    Does anyone got the script of this video?

  • Literally Felicity
    Literally Felicity 22 дня назад

    What a clear explanation, even people that are not familiar with cryptocurrencies can grasp this.

  • JB
    JB 22 дня назад

    4:30-5:00 is a great summary.

  • Menasha de Silva
    Menasha de Silva 23 дня назад

    thank you! this pace was easy to keep up with. the graphics helped as well.

  • Mindaugas Žilionis
    Mindaugas Žilionis 24 дня назад

    This explanation gives a very good explanation of a principle, but I still struggling to understand how money can be sent from USA to Germany by not using banking system.

  • David Appleseed
    David Appleseed 24 дня назад

    You saved me for my AP project because this explained everything i needed

  • In4cer in4cer
    In4cer in4cer 25 дней назад

    Thanks for what you are doing. Just discovered your site.

  • Paul M
    Paul M 25 дней назад

    Thanks that makes sense. The term 'blockchain' is so weird. Nothing intuitive about its meaning!

  • BLiNK like Limario
    BLiNK like Limario 26 дней назад

    Where my fellow ENP students at?

  • Brad Smith
    Brad Smith 26 дней назад

    Neat project!

  • John Cena
    John Cena 26 дней назад

    Your voice sounds like Great Scott's voice!

  • Thanin Thavonsassanavong
    Thanin Thavonsassanavong 26 дней назад

    Dear Xavier,
    Thanks so much for the video which really simple and very easy to understand the basic concept
    of blockchain technology.
    By the way, at the 1:15 minute from the "How does a blockchain work video", you explained that the data
    in the bitcoin transaction will have only the "From" (Sender), "To" (Receiver) and "Amount"
    (amount of bitcoin to be send) data.
    But, May I wonder how the blockchain node could know that the sender has enough amount of bitcoin to send and
    how the blockchain node update the amount of bitcoin in the sender and receiver wallet?
    Thanks so much in advance for your kindly advice,.

    • Simply Explained - Savjee
      Simply Explained - Savjee  20 дней назад

      Sure! It's actually really simple. Each node on the network knows about all the transaction that have ever happened on the blockchain. If I received 6 transactions of 10 coins, then each node can calculate that my balance is 60 coins. So in summary: checking the balance of a wallet means checking all the transactions to and from that wallet.

  • MyCatFooed
    MyCatFooed 27 дней назад

    This seems easily beatable to me. All you need, other than many very powerful computers, is a fellow group of conspirators -- The 51% result would be simple to achieve quickly, and further, higher %s appear theoretically possible, as long as you limit the new members of the chain and maintain the integrity of your fellow cohorts.
    System beaten. No?

    • Simply Explained - Savjee
      Simply Explained - Savjee  20 дней назад +1

      It depends on the size of the blockchain network. In Bitcoin's case it is going to be pretty hard to get that much computing power. But on smaller blockchains it's trivial (like you said). So the system is indeed beatable, especially proof-of-work. That's why many projects are working on new consensus algorithms (like proof-of-stake) to balance this.

  • Banking Innovations
    Banking Innovations Месяц назад

    Amazing and very "simply explained". Never seen such a simple animation for conceptualization of a technology. Kudos to the makers. Love it.

  • JK Hunter
    JK Hunter Месяц назад

    Great simplified explanation! Thank you!

  • answerBACK-films
    answerBACK-films Месяц назад

    I have never understood "proof of work" as a valid way to make the blockchain tamper proof. What exactly does the computer solving a puzzle have to do with proving a transaction was/is valid...this is bizarro world. And whats more it has to be first, like winning a prize...and then, irrelevant puzzle solved, this proves the transaction took place, somebody paid for a pizza somewhere" HOW DOES THIS PUZZLE WORK PROVE ANYTHING about the transaction it is fighting to prove is valid..

    • Simply Explained - Savjee
      Simply Explained - Savjee  26 дней назад

      Hang on, these are two different things! Proof-of-work doesn't verify the transactions inside a block. It's just a way to slow down the creation of blocks. It's a reliable way to prevent people from making a ton of blocks at once.
      Verifying transactions is something else. To do that, the miner checks that each transaction was signed with the correct keys (eg the key of the person who sends the money). It also checks if that person has a high enough balance to make that transaction.
      Hope that makes more sense now ;)

    NSS IPM VN Месяц назад

    Great work

  • Tiffany LaBruno
    Tiffany LaBruno Месяц назад

    totally agree I finally get it...well done

  • Akin Akinrinade
    Akin Akinrinade Месяц назад

    So blockchain is an implementation of linked list. If you remember that course 'Data Structure'

    • Simply Explained - Savjee
      Simply Explained - Savjee  Месяц назад

      Absolutely! It's like a linked list with some additional properties to prevent tampering.

  • Dominic Candy
    Dominic Candy Месяц назад

    Excellent beyond all standards!!!!

  • Majd Sahmarany
    Majd Sahmarany Месяц назад

    Fine work..

  • universalsheep
    universalsheep Месяц назад

    you should say "if the UID of the block changes" instead of fingerprint. fingerprints arent unique

    • Simply Explained - Savjee
      Simply Explained - Savjee  Месяц назад

      Sure, but UID's are difficult for people to understand. Fingerprints are easy to understand (and they are unique enough to use an example)

  • jayesh PATOLE
    jayesh PATOLE Месяц назад

    Can block chain be Next internet????

    • Simply Explained - Savjee
      Simply Explained - Savjee  Месяц назад

      Yes it can! Check out my video on IPFS which uses a Blockchain-like system to do just that!

  • Gary Fox
    Gary Fox Месяц назад

    Really well explained. Nice video & style.

  • Cloudy Geek
    Cloudy Geek Месяц назад

    another not so good explanation by someone who is not a dev

  • May Rose
    May Rose Месяц назад

    Only way this works is to replace the people shown here as miners with computers. I'm not buying it. This will be great for hackers and manipulators. There is no way that people will be able to manage hundreds of millions of transactions daily to add to ledgers.

  • Figable
    Figable Месяц назад

    Great explanation! How does each of the members know how to "verify" a block?

  • Jannatul Ferdausi
    Jannatul Ferdausi Месяц назад

    Really like your wonderful explanation. Thank you very much.

  • Guttini
    Guttini Месяц назад


  • Zachary Quinn
    Zachary Quinn Месяц назад

    it's a linked list, but instead of memory address information, it's hashes. interesting. that's not a new concept by any means.

  • Joseph Kolarz
    Joseph Kolarz Месяц назад

    THank you

  • Siva Paranitharan
    Siva Paranitharan Месяц назад

    Savjee! Thank you. You are very easy to follow and superbly illustrated. Kindly keep doing more. Best Regards

  • Jeremy Thompson
    Jeremy Thompson Месяц назад

    Can you restrict yourself to the peers you consider "legitimate"?

    • Jeremy Thompson
      Jeremy Thompson Месяц назад

      +Simply Explained - Savjee Does this solve the 51% problem, then?

    • Simply Explained - Savjee
      Simply Explained - Savjee  Месяц назад

      This is the default behavior of most Blockchain implementations. They'll just ignore bad actors or even ban them.

  • Iisa Jenkins
    Iisa Jenkins Месяц назад

    I want to learn how to trade forex

  • ColorMysteries
    ColorMysteries Месяц назад

    Cryptocurrency is the future. It is just a matter of time.

  • Dilan Sharma
    Dilan Sharma Месяц назад

    Investing cryptocurrencies is also a safe means of saving.

  • LeahSephira
    LeahSephira Месяц назад

    Thank you for this explanation, it was simple and to the point. At least I understand it now :)

  • IETCHX69
    IETCHX69 Месяц назад

    Seriously ? Thank you . You dig ?

  • Hieu Luong
    Hieu Luong Месяц назад

    The proof of work is still not clearly explained.

  • mohit bansal
    mohit bansal Месяц назад

    Super Simple. The first time I think somebody is trying to explain you and not confuse you on this topic.

  • Khilna Mamlani
    Khilna Mamlani Месяц назад

    thanks.. well explained

  • Konseq
    Konseq Месяц назад

    Did you just delete my comment to your video??

    • Simply Explained - Savjee
      Simply Explained - Savjee  Месяц назад

      No, didn't see any comment. It's possible that youtube marked it as spam.. Not much I can do about that I'm afraid.

  • Future Done Right-TM
    Future Done Right-TM Месяц назад

    Very helpful. Thanks for making it so simple. That's what I did with my book. I worked to make the business uses of blockchain very simple so people get it.
    Too much blockchain talks past people.

  • Valter Zikovic
    Valter Zikovic Месяц назад

    Thank you.

  • Craige Banios
    Craige Banios Месяц назад +6

    What happens if someone (Federal Reserve) dominates the mining for a certain (or all) crypto currency? Could someone with enough computing power steal everyone's "money?"

    • rightchain yi
      rightchain yi 9 дней назад

      I have a project that you might be interested in.

    • pkay dennis
      pkay dennis 19 дней назад

      the current banking system (fiat)

    • Craige Banios
      Craige Banios Месяц назад

      Thanks Savjee (If that's your name). I thought that would be the case from your other explanations along with a few other folks input. :)

    • Simply Explained - Savjee
      Simply Explained - Savjee  Месяц назад +2

      Actually that would be possible. If you can gather more than 50% of all the computing power on the network, you can approve any transaction you want. Even fake or fraudulent ones. On big networks like Ethereum and bitcoin it's hard and expensive to achieve this, but possible non the less!

    • Craige Banios
      Craige Banios Месяц назад

      Tell me why you say that. Or direct me to an explanation of such please. Thank you.

  • Vishal Thokade
    Vishal Thokade Месяц назад +2

    It says: adding a block needs to have consent of all the members which is impossible to do. Does it mean that one can never add a block to a chain?

  • Technigeek
    Technigeek Месяц назад +10

    nice simple explanation , but there is one note i wanted to say , there is a method hackers have managed to make its called the %51 attack , which is taking over the blockchain by having the power of hashing controlled by super huge miners that can make more than 50% of the hashing power of the blockchain , so they can manage the next block as they want , they will inject a block with information that benefit them , in anothet words , they steal other peoples coins , this is a sneaky way for taking over the blockchain, even though it looked impossible before , but now its not impossible any more

    • the black panther
      the black panther 17 дней назад +1

      I agree with you 100per cent thanks for telling it like it is. Keep it real 24/7.

    • pamanudavy
      pamanudavy 25 дней назад +1

      @actually he mentioned it at 4.46 but he was not interested in explaining it.

    • Sentinel of Fortune
      Sentinel of Fortune 27 дней назад +2

      Which is why we have decentralization my friend

    • Josiah Umezurike
      Josiah Umezurike Месяц назад

      You are correct it assume only 1/3 of the participators are bad guys. Therefore the 51% attack is being used mostly in Asia regions. This allows you to control the mining thus consensus PoW.

    • Craige Banios
      Craige Banios Месяц назад

      Technigeek Can you say, "Federal Reserve?"

  • Purnima Gupta
    Purnima Gupta Месяц назад

    this is superb..thanks

  • Gaming Champ
    Gaming Champ Месяц назад

    Hi , I really like this topic blockchain and adding some important topics as well in youtube and linkedin for blockchain please see the link

  • Lorenzo Luiz De Souza
    Lorenzo Luiz De Souza Месяц назад

    Hackers be like, "Challenge accepted"

  • Miguel G
    Miguel G 2 месяца назад

    sorry if this sounds like a stupid question (still trying to understand blockchain), but would a faulty genesis block then ruin the entire chain? I'm thinking along the lines of fake news and misinformation. If the genesis block contains faulty data to begin with, and a chain is created from this genesis block, would this then be difficult to fix because of how difficult it is to change data?

    • Simply Explained - Savjee
      Simply Explained - Savjee  2 месяца назад

      There are no stupid questions! The genesis block is almost like a dummy block. It contains almost no data. In theory you could use a Blockchain to store fake news, and yes, it would be impossible to remove it later on... That's true for the Genesis block but also for any subsequent blocks.

  • Cheeky Nham
    Cheeky Nham 2 месяца назад

    Nothing is impossible in this day and age. Technology evolves all the time, and someone will figure out how to tamper.

  • Aditya Sawdekar
    Aditya Sawdekar 2 месяца назад

    Very wonderfully explained. Finally I got it

  • fábio
    fábio 2 месяца назад

    Thank you for saving my presentation!

  • Charlikins
    Charlikins 2 месяца назад

    Finally after all my research I know nothing about blockchain. this makes no sense.

  • Ramanan austin
    Ramanan austin 2 месяца назад

    What will happen if millions of blocks are created at once and how will a user authenticate every single one of them ?

    • Ramanan austin
      Ramanan austin 2 месяца назад

      Thank you for patiently answering my questions

    • Simply Explained - Savjee
      Simply Explained - Savjee  2 месяца назад

      Yes, at least half of the network has to approve the new block. If not, the block is rejected. It is possible that two poeple create a valid block at the same time. This is a natural fork. The network however only chooses one of the blocks and builds on top of it. The other block becomes stale and transactions inside will be re-executed.

    • Ramanan austin
      Ramanan austin 2 месяца назад

      So all or 50% of the 2000 has to authenticate the new block? And a problem will raise when more than 1 wants to create a new block at the same time ?

    • Simply Explained - Savjee
      Simply Explained - Savjee  2 месяца назад

      Depends on the Blockchain. Bitcoin for instance can store a maximum of 2000 transactions per block. Others might have a lower or higher limit.

    • Ramanan austin
      Ramanan austin 2 месяца назад

      How many users can a single block have ?

  • Daria Zueva
    Daria Zueva 2 месяца назад

    I still don`t understand

  • sha li
    sha li 2 месяца назад

    thank you ! your explanation are so easy to understand.

  • Max Gillespie
    Max Gillespie 2 месяца назад

    This is super clear and to the point. Thanks so much!!

  • aranguren12
    aranguren12 2 месяца назад

    Hello Savjee, thank you for this video. I´d like to ask you if the illustrations used in this video can be used in academic papers . (Attributed of course)

  • anon ymous_user
    anon ymous_user 2 месяца назад

    Good explanation, also useful for getting to sleep. Sorry but true.

  • noodlefoo
    noodlefoo 2 месяца назад

    I still don't know what type of data is contained in a block.

    • Simply Explained - Savjee
      Simply Explained - Savjee  2 месяца назад

      A transaction is stored on the blockchain when you send or receive some Bitcoin. If you buy something with Bitcoin there is a transaction created where you send X amount of coins to a store for example. So, if you do a transaction with Bitcoin, it's stored inside the chain.

    • noodlefoo
      noodlefoo 2 месяца назад

      What and whose transaction data? The banks? Retail shops? Online purchases? Illegal transactions at dark web?

    • Simply Explained - Savjee
      Simply Explained - Savjee  2 месяца назад

      It's mentioned in the video. Bitcoin blocks for instance contain transaction data (for sending and receiving money).

  • David Regourd
    David Regourd 2 месяца назад

    great explanation, thanks

  • Ashish Pandey
    Ashish Pandey 2 месяца назад

    This is superb man, thanks for sharing !

  • Mr. Right
    Mr. Right 2 месяца назад

    Is it possible for a virus to analyze the hash and replace it making the other blocks think that nothing happened. Is it a mix of human and computer algorithms or just computer?

    • Simply Explained - Savjee
      Simply Explained - Savjee  2 месяца назад +2

      Yes, a virus can do that. In fact: you can change anything you want because it's your copy of the Blockchain. However, all your changes are only local and you won't be able to 'convince' the other computers on the network that your changes are the 'truth'. They will just reject them.

  • Aakash Calmly
    Aakash Calmly 2 месяца назад

    Does anyone know what kind of animation software is supposed to be used to make such videos?

  • omar isaid
    omar isaid 2 месяца назад

    Simple , useful , and clear . Thank you

  • Teresa Miller
    Teresa Miller 2 месяца назад

    Goals! 👌🏼

  • chi cong Nguyen
    chi cong Nguyen 2 месяца назад

    Hay hay

  • Sachin Kainth
    Sachin Kainth 2 месяца назад

    I thought hashes were not unique!

    • Simply Explained - Savjee
      Simply Explained - Savjee  2 месяца назад +1

      Well, technically we can't guarantee that a hash will always be unique. But the chances of 2 different things producing the same hash is very small (and new hash algorithms try to make it even smaller). When 2 different pieces of data produce the same hash, we have a "hash collision".

  • Neil Canfield
    Neil Canfield 2 месяца назад

    Digital Amway. Serious question though.I know knothing about Bitocin or BC but this video has helped. Let's say I want to buy some Bitocoin form you Coinbase link Do i Just go to that link and create a UN and PW and make a transaction by transferinf funds from my bank to the Bitcoin? DO i have to create a wallet? or do I get a confirmation email with my Hash saying thank you for your purchase?

    • Simply Explained - Savjee
      Simply Explained - Savjee  2 месяца назад

      Coinbase manages everything for you and they make it pretty easy. You transfer money to them and they put your dollars/euros into your account. Afterwards you can use your dollars to purchase bitcoin. Again coinbase will handle the creation of a wallet automatically.

  • geneiuspower
    geneiuspower 2 месяца назад

    yaaaaaaaaaaaaaaaaa still confusing . it's just funny that humans make simple things seem complex when it's actually not .

    • Simply Explained - Savjee
      Simply Explained - Savjee  2 месяца назад

      So you're saying you're confused but that it's not complex at the same time? Huh?

  • Justin H.
    Justin H. 2 месяца назад

    Wont this only continue to work if everyone online stays anonymous. What about when were all chipped and you can identify who's who?

    • Simply Explained - Savjee
      Simply Explained - Savjee  2 месяца назад

      Uhm... ¯\_(ツ)_/¯
      Kind of a weird question. Blockchain doesn't have to be anonymous to work.

  • jesusfernan39
    jesusfernan39 2 месяца назад

    Great job! I finally got it.

  • Abdul Latheef
    Abdul Latheef 2 месяца назад


  • CellBot
    CellBot 2 месяца назад

    nice vid

  • Cristi M
    Cristi M 2 месяца назад

    Is this the guy from Slivki show ? It's the same voice

  • Prasanth Touchlive
    Prasanth Touchlive 2 месяца назад

    thank you

  • Nuredin Seci
    Nuredin Seci 2 месяца назад

    so nodes are mining here? so how do mining verify transactions? and who provides the puzzles for miners?

  • Knowledge Nation
    Knowledge Nation 2 месяца назад

    This RU-clipr definitely needs a 1M subscribers! Than 'boring' RU-cliprs like MKBHD or 'phycho' like unbox therapy. I need a therapist for watching his videos!!:0

  • Kirandas R
    Kirandas R 2 месяца назад

    its same as linked list with extra linked list V2

  • Asker Akram
    Asker Akram 2 месяца назад

    Simple and brief! Excellent work! Thank you!