[Video] What is Segwit? (Segregated Witness)

Last updated on January 2nd, 2018 at 12:00 am

In today’s video we’re going to talk about a term you may have heard bouncing around lately. I’m talking about “Segregated Witness” or Segwit in short.
IMPORTANT: Segwit includes a wide range of features, many of which are highly technical. In this video we focus on one main feature that is easier to explain.

Segwit was invented in order to help shrink the file size of a Bitcoin transaction. This allows more transactions to be approved each time a block of transactions is confirmed. Basically, its purpose is to make the Bitcoin network approve more transactions with each block.

Every Bitcoin transaction has 3 parts – who sent it, who receives it, and a digital signature that verifies the sender has the right to send the coins. The signature is considered to be “the witness” for the transaction.

Segregated Witness means that we are separating the witness from the transaction in order to make it smaller in size. The signature data, or witness,  will still be transmitted, however it won’t be included inside of the transaction.

What’s special about Segwit is that a consensus of the entire Bitcoin network isn’t required in order to make it work. This is known as a “soft fork” – meaning Segwit will work even if some users don’t update their software to the new version, making it much easier to implement.

To conclude Segwit is a method of scaling the Bitcoin network to confirm more transaction on each block without increasing the block size itself. I hope you enjoyed this video, and I’ll see you in the next one. Bye for now!

For more information about Segwit’s benefits here’s a complete resource.

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  1. Great video! The simply-explained content here is exactly why I always recommend 99Bitcoins to people who are new to Bitcoin.

    Is Segwit only a temporary solution for the high transaction fees? Would we face the same problem again when Bitcoin’s popularity gets to an even larger size?

    • Yes, Segwit won’t be able to withstand huge transaction volumes once the general public gets in on Bitcoin. However, it’s the basis for other developments that will allow this such as Lightning Network. So I’d say we’re on to a good start.
      Thanks for the compliments I really appreciate it.

  2. I’m not an advance bitcoin guy, but something seems to be missing from the video/paragraph. I think it comes down to two questions:

    1) If Segwit is such a good idea, why is it only coming out now?
    2) What is the downside (if any) of not including the signature inside the transaction?

  3. miketwenty1 on

    Segwit is not for just creating more space for transactions (that’s almost like a side effect). If that were the case they would just up the blocksize. Witness data should still be held by nodes that want all the data to validate previous transactions. There are multiple improvements when using Segwit such as validating transactions and fixing stuff like transaction malleability.

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