What are Bitcoin Blocks and Bitcoin Confirmations ?

Let’s say I send you 1 Bitcoin. After a few minutes you see that this transaction has received one “confirmation”. What does this actually mean?

The block chain is built out of “blocks”. Each new block is a set of new unique Bitcoin transactions that were recently made. So when I broadcasted to the network that I want to send you 1 Bitcoin the transaction went into an unconfirmed transactions pool.

Miners entered the unconfirmed transactions pool, took this transaction and others like it, verified they were valid (meaning I actually have the 1 Bitcoin to spend), and grouped them into a block. The new block is set at the top of the blockchain and is considered confirmed. Now miners can move on to build the next block on top of that one.

Each time a new block is built it means that the older blocks got confirmed again (since they are checked also in the process). The more confirmations you get, the harder it will be for someone to manipulate the system and remove the block containing this transaction from the wall (or blockchain) since it’s buried under the other blocks that were confirmed.

It is recommended to wait for at least 6 confirmations in order to be 99.9% sure that your transaction won’t get canceled – this takes roughly 1 hour to achieve. If you’re dealing with smaller amounts of money you’re probably OK with waiting for just 1 confirmation.

Reversing a transaction takes planning, time and effort and a lot of computing power. Most people probably won’t go through all of that trouble for a small amount of money.

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Samurai
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Samurai

Hi i have one question. I use blockchain miner pro and i need comfirmations to transfepere my BTC from program wallet to my real wallet (i mean to paypal) so how i can get confirmations ?

Alyxs
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Alyxs

how many good share i have to make for confirmation block

ExMachina
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ExMachina

I have some questions. How exactly do all miners share the same ledger? I mean, if miner goes offline for a bit, he would need to refresh his ledger, how would he do that and how would he confirm integrity of the new blocks? Would he just update the ledger from several different nodes? What if those nodes contradict with each other? What if more than a half of those nodes are compromised? Is blockchain vulnerable to sybil attack in general?

john borrow
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john borrow

I am mining a small amount of bitcoin on the Genisis platform. I don’t want to sell, but if I did, how would I do this? I can’t see any sell options anywhere on the site..

John Borrow

rawlings frakenstein
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rawlings frakenstein

How to make profit through buying and selling of bitcoins

Mulaa
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Mulaa

I don’t know how I stumbled on this blog and after a few videos I can say it is awesome

JAMES JOHNSON
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JAMES JOHNSON

my transaction pending with bitcoin for two days

BRIGHT OMOAREBU
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BRIGHT OMOAREBU

Thanks a bunch, Ofir. I am really learning much and uping my knowledge in Bitcoin.

muhamma dasuki bin khaaja kamarudin
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muhamma dasuki bin khaaja kamarudin

Tq So Much.. This video..

vittorio
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vittorio

I am really enjoying this videos.
thanks