What is a Bitcoin in my computer? An archive, an abstract value?

[GussRosa]

Hello folks.

Sorry, this must be a very silly question, but it's a doubt i have for quite some time.

What is a Bitcoin when it's stored in my wallet? Is it a findable archive in my computer? or it is something more abstract?

Thank you.

[albert11]

a wallet on your computer is a private key file


bitcoins are not stored on your computer, they are on the blockchain, so when you say you have bitcoins it means that you have ownership of the public address,

[ebliever]

Bitcoin exists in the form of a ledger shared across the bitcoin network, listing transactions between addresses/accounts. Only there in the ledger (called a blockchain) does bitcoin really "exist". You "own" a bitcoin when you have password access/control over the private keys that control bitcoins sent to you (or mined by you) on the blockchain, enabling you to initiate a transfer to a new address on the blockchain ledger.

The wallets people talk about on their computers don't hold bitcoins as such; they just contain the public and private keys that enable you to receive and send bitcoins, hopefully with good password control on the wallet itself. The wallet also ties into the blockchain to provide you with balance information and a transaction history. But the blockchain is the authority, and the only place a bitcoin really resides.

That's my take on it, anyway.

[kpitti]

Your wallet is just presenting your ownership of Bitcoins addresses you have. Because you have private keys for them.
Bitcoins are stored in Blockchain as Ledger.

[runpaint]

Bitcoin is a network of computers.  Coins are generated as a reward for securing and maintaining the network.  

Your bitcoin is a symbol which represents the work which was done to generate it, and the coin allows you access to use the network.  

The coin exists only on the network, as a series of unforgeable transactions which prove the coin's authenticity from now back to the moment it was generated.  A valid amount of coins shows how much of the network's resources you are entitled to use, and we know the coin is valid because we know you received it from its previous valid owner.  We know the previous owner was valid because we know where he got it, and so on.

The "thing" that exists on your computer is a private key (a password or code) to your wallet address, which allows you to access your coins on the network.  Even if you spend all your coins, nothing is different on your computer.  You still have the same private key, but the network shows that the coins have moved from your address to someone else's.

[OnkelPaul]

Here's an example that's not entirely accurate but easily understandable:
Your wallet file is like a keyring - it holds the keys for your own bitcoin addresses.
Imagine a huge room full of safe deposit boxes. Each box corresponds to a bitcoin address and has a door that can only be opened with the correct key. In addition, it has a slit through which bitcoins can be put into the box but not retrieved. Everybody can enter the room and see how much is contained in each box. This room is the blockchain.
Whenever you create a new address, a box with that address "magically appears" but nobody can see it in the room before someone puts some bitcoin value into it because the blockchain does not store addresses but only payments to addresses (this is simplified, there are some other special kinds of payments).
Since you can create an arbitrary number of addresses, it is not easily possible to see which addresses belong to you. When someone sends you money, they know that the address they're sending to is one of yours, but they don't know your other addresses. If you send money from one of your addresses to someone else, they will know that you're the owner of that address. Therefore it is advisable to use each address only once (unless you're ok with tracability of your transactions, for example when you're a charity.)
When you lose a key, you can't access the value stored in its box anymore, and when a key is copied by a thief, they can access your box just like you could.
So you need to protect you wallet against loss and against unauthorized access.
Loss can be prevented by backing up your wallet file regularly, while theft can most easily be prevented by protecting the wallet file with a strong (unguessable) passphrase. Of course, when the computer on which you access the wallet file becomes compromised (keylogger etc.) then the keys in your wallet can be copied by a thief, so you need to be extra careful about this.

Onkel Paul

[nikona]

Here's an example that's not entirely accurate but easily understandable:
Your wallet file is like a keyring - it holds the keys for your own bitcoin addresses.
Imagine a huge room full of safe deposit boxes. Each box corresponds to a bitcoin address and has a door that can only be opened with the correct key. In addition, it has a slit through which bitcoins can be put into the box but not retrieved. Everybody can enter the room and see how much is contained in each box. This room is the blockchain.
Whenever you create a new address, a box with that address "magically appears" but nobody can see it in the room before someone puts some bitcoin value into it because the blockchain does not store addresses but only payments to addresses (this is simplified, there are some other special kinds of payments).
Since you can create an arbitrary number of addresses, it is not easily possible to see which addresses belong to you. When someone sends you money, they know that the address they're sending to is one of yours, but they don't know your other addresses. If you send money from one of your addresses to someone else, they will know that you're the owner of that address. Therefore it is advisable to use each address only once (unless you're ok with tracability of your transactions, for example when you're a charity.)
When you lose a key, you can't access the value stored in its box anymore, and when a key is copied by a thief, they can access your box just like you could.
So you need to protect you wallet against loss and against unauthorized access.
Loss can be prevented by backing up your wallet file regularly, while theft can most easily be prevented by protecting the wallet file with a strong (unguessable) passphrase. Of course, when the computer on which you access the wallet file becomes compromised (keylogger etc.) then the keys in your wallet can be copied by a thief, so you need to be extra careful about this.

Onkel Paul

great explanation man.. I used to have some doubts too but now it is all clear.. thank you

[DannyHamilton]

Hello folks.

Sorry, this must be a very silly question, but it's a doubt i have for quite some time.

What is a Bitcoin when it's stored in my wallet? Is it a findable archive in my computer? or it is something more abstract?

Thank you.

You are asking a very technical question.

The surprising answer is that bitcoins don't exist at all.

There is nothing that you can point at and say "that's a bitcoin".  There is no file, or sequence of letters or numbers that represents a singe bitcoin.  The concept of "a bitcoin" is an abstraction that we humans use to make it easier to talk about the transfer of control of value.  For that matter, there are no "addresses" at the protocol level either.

There is a blockchain, which is an ordered list of every transaction that has ever occurred.

With the exception of one "generation transaction" in each block, transactions typically include a list of previously unspent outputs that are being used to supply value to the transaction, and a list of new unspent outputs, each assigned some portion of the total transaction value supplied by the inputs, that are encumbered with requirements that must be met in order to use the new unspent outputs as inputs to a transaction.

Typical outputs are encumbered with a requirement to supply an ECDSA digital signature generated with a private key that is associated with a specific hash of a public key.  This public key hash is a numeric value between 1 and 1.46X10⁴⁸.  In order to tell someone how to properly encumber their outputs so that you are able to provide the necessary signature, you need a reliable way to give them this public key hash.  A version number is pre-pended to the hash value, and a checksum is appended to the the hash value to prevent typos from causing a problem.  Then the entire value is represented in base58 using letters and numbers.  This versioned, check-summed, base58 encoded hash value is what we call a "bitcoin address".  By giving this value to someone, their wallet can extract the hash value from the address, verify the check sum, and then add the proper encumbering onto the output of the transaction that the wallet creates.

[oblivi]

https://www.youtube.com/watch?v=J8y_GypCWf4

Andreas addresses this in this video. It's basically a password that only you know... there are no coins, and there are no wallets. But the terminology makes us think of coins and wallets when it's just private keys.

[cryptosky]

actually you have no bitcoin in your computer,you only have the key of some bitcoins in a blockchain address

[Beliathon]

actually you have no bitcoin in your computer,you only have the key of some bitcoins in a blockchain address

Bingo. You're storing keys which allow control over some amount of btc. Ownership does not apply on the blockchain.

[Kprawn]

I see it like this...

You have access to a public ledger through a bitcoin address that points to the collection of bitcoins you own... to prove that you are the owner of those bitcoins or a portion of it, you are supplied with a secret key.

The bitcoin address and the secret key is linked to each other through VERY complex mathematical algorithms.

The secret key, is your proof, that you own the coins.  

[GussRosa]

Thank you all 

[mlferro]

Your wallet is just presenting your ownership of Bitcoins addresses you have. Because you have private keys for them.
Bitcoins are stored in Blockchain as Ledger.

his response was perfect.

[Lorenzo]

Everyone who is running the Bitcoin program has a long list of transactions stored in a file on their computer called the blockchain. Transactions occur between addresses that look like random strings of uppercase and lowercase letters and numbers such as 1H9AaiUjuPzTtHD99FxsBGhWFuZgPUrc5M. These computers communicate with each other so that the blockchain that exists in every single computer is identical.

What you might also have is something called a "private key". This is a little bit of text that can be used to unlock an address that may or may not contain bitcoins. If you have a private key that unlocks an address containing 1,000 BTC, then you effectively have control of 1,000 BTC. If you have a private key that unlocks an address containing 0 BTC, then you have control of 0 BTC. The blockchain is the same for everyone but having a private key grants you ownership of that address and thus the ability to send transactions via that address.

A wallet is really just a collection of private keys. You can even ditch the computer altogether and scribble the private key on a piece of paper and those bitcoins will still be under your control.

[Lauda]

Well one could somehow compare your computer with a bank, and say that it is your own bank. Depending on the security level of it, your funds are either safe, or not.

[jonald_fyookball]

the coins are actually inside your mouse... you can access them by removing that little battery cover, pulling out the battery and then shaking really really hard.  if that doesn't work, reboot your mousepad and try it again.

[ikydesu]

Hello folks.

Sorry, this must be a very silly question, but it's a doubt i have for quite some time.

What is a Bitcoin when it's stored in my wallet? Is it a findable archive in my computer? or it is something more abstract?

Thank you.

When bitcoin store on your wallet, that bitcoin will be your mine.
bitcoin on your comp is just numeral, but have a value when you exchange.


~iki

[ToshiOcean]

I don't know about the OP, but I'm saving a copy of this thread. All of these replies are outstanding, and extremely helpful.

[LiteCoinGuy]

here are your Bitcoins:




 

sorry, no coins 


@ToshiOcean

not mine