Private key and public key

[demsybtc]

Hi guys,

What are the differences of public keys and private key? What are they used for? Can I only have one key?

[1714844488]

1714844488

[escrow.ms]

I think this article explains it properly.

http://chimera.labs.oreilly.com/books/1234000001802/ch04.html
and read this as well.

http://bitzuma.com/posts/six-things-bitcoin-users-should-know-about-private-keys/

[Darkoth89]

I suppose you know the concept of public key cryptography? If you don't, here is a very short explanation: Public key cryptography (as used in Bitcoin), allows you to hand people a public key and use the corresponding private key to prove the ownership. So you can create any random private key (keep it secret) and calculate the corresponding public key (give it out to public for verification). Using this private key, you can sign a message and other people can verify that you own the private key by using your public key.

So, applied to Bitcoin.

A Bitcoin address is just a shorthand notation for a public key. When someone makes a transaction to an address, he states that "I give the right to spend this money to the person who owns the private key corresponding to this address". The person who has received this transaction will in turn be able to spend the transaction by signing the transaction using his private key. With this signature he can prove that he owns the key, without disclosing it. Others can verify the signature using the public key.

As for the second part of your question, if you download a bitcoin wallet, you can have as many different addresses as you wish.

[demsybtc]

I suppose you know the concept of public key cryptography? If you don't, here is a very short explanation: Public key cryptography (as used in Bitcoin), allows you to hand people a public key and use the corresponding private key to prove the ownership. So you can create any random private key (keep it secret) and calculate the corresponding public key (give it out to public for verification). Using this private key, you can sign a message and other people can verify that you own the private key by using your public key.

So, applied to Bitcoin.

A Bitcoin address is just a shorthand notation for a public key. When someone makes a transaction to an address, he states that "I give the right to spend this money to the person who owns the private key corresponding to this address". The person who has received this transaction will in turn be able to spend the transaction by signing the transaction using his private key. With this signature he can prove that he owns the key, without disclosing it. Others can verify the signature using the public key.

As for the second part of your question, if you download a bitcoin wallet, you can have as many different addresses as you wish.

Meaning for instance, if I want to transfer $100 to u, I'll hand u my public key, thereafter I'll use my private key to identify myself as the authentic user? Meaning there's no harm for anyone to know my public key right? It's the private key which is utpmost importance

[BitcoinSupremo]

I suppose you know the concept of public key cryptography? If you don't, here is a very short explanation: Public key cryptography (as used in Bitcoin), allows you to hand people a public key and use the corresponding private key to prove the ownership. So you can create any random private key (keep it secret) and calculate the corresponding public key (give it out to public for verification). Using this private key, you can sign a message and other people can verify that you own the private key by using your public key.

So, applied to Bitcoin.

A Bitcoin address is just a shorthand notation for a public key. When someone makes a transaction to an address, he states that "I give the right to spend this money to the person who owns the private key corresponding to this address". The person who has received this transaction will in turn be able to spend the transaction by signing the transaction using his private key. With this signature he can prove that he owns the key, without disclosing it. Others can verify the signature using the public key.

As for the second part of your question, if you download a bitcoin wallet, you can have as many different addresses as you wish.

Meaning for instance, if I want to transfer $100 to u, I'll hand u my public key, thereafter I'll use my private key to identify myself as the authentic user? Meaning there's no harm for anyone to know my public key right? It's the private key which is utpmost importance

Correct. For more information read this article as it explains in deep the technical details for you, but normally is as you say, the private key is the one with utmost importance as anyone who have it can spend the bitcoins from that address.

http://www.dummies.com/software/other-software/bitcoin-public-private-keys/

[demsybtc]

in that case needs to really secure and protect the private key, anyone else holding your private key is as good as holding your bitcoins. thanks for the sharing

[Mike Mayor]

in that case needs to really secure and protect the private key, anyone else holding your private key is as good as holding your bitcoins. thanks for the sharing

Yes ! Keep your private key back up everywhere !! Go crazy with it. You can never have enough back ups. Please do yourself a huge favour and print out the private key and put it in your safe. This is also known as a paper wallet. Though a paper wallet printout is more fancy and nicer. Also don't backup an uncrypted or none password protected private key to any device that can connect online. Keep it offline if possible.

[odolvlobo]

Some clarification of terms would help here:

• Private key - A value that allows you to spend the bitcoins at the address associated with it. Anyone that knows the private key for an address can spend the bitcoins at that address.
• Address - In simple terms, an address holds bitcoins. It is frequently (and incorrectly) called a "public key". It is not a public key. It is also frequently (and incorrectly) called a "wallet". It is not a wallet.
• Wallet - A container holding one or more private keys and their associated addresses. Also, it typically includes software that maintains the wallet, connects to the Bitcoin network, and creates transactions.
• Seed - A unique value used by a wallet to generate all of its private keys. This is also sometimes referred to as a "recovery phrase". Anyone that knows a seed can create the wallet that uses it and spend all the bitcoins in it.
• Password or passphrase - A password may be used to encrypt the data in the wallet. This is not a seed.

[Considered]

I think this article explains it properly.

http://chimera.labs.oreilly.com/books/1234000001802/ch04.html
and read this as well.

http://bitzuma.com/posts/six-things-bitcoin-users-should-know-about-private-keys/

Some clarification of terms would help here:

• Private key - A value that allows you to spend the bitcoins at the address associated with it. Anyone that knows the private key can spend the bitcoins.
• Address - In simple terms, an address holds bitcoins. It is frequently (and incorrectly) called a "public key". It is not a public key. It is also frequently (and incorrectly) called a "wallet". It is not a wallet.
• Wallet - A container holding one or more private keys and their associated addresses. Also, it typically includes software that maintains the wallet, connects to the Bitcoin network, and creates transactions.
• Seed - A unique value used by a wallet to generate all of its private keys. This is also sometimes referred to as a "recovery phrase". Anyone that knows the seed can recreate the wallet and spend all the bitcoins in it.
• Password or passphrase - A password may be used to encrypt the data in the wallet. This is not a seed.

Thank you for lighting me up.