What is a cryptocurrency private key?
A cryptocurrency private key is a secret string of characters used to spend cryptocurrency, for example Bitcoin. When someone generates a Bitcoin address for himself, he gets a public key and a private key. The public key is used to receive cryptocurrency, and can be shared with the outside world. Most people call it their Bitcoin wallet address. An example of a Bitcoin public key is:
You can send this address to anyone who wants to transfer Bitcoin to you. When the wallet address is generated, a private key is also created. This is a 256 bits number consisting of 64 characters. There is only one private key for each address and it is the unique key to the wallet. With this key you put a digital signature, showing that you are the owner of the wallet. An example of a private key is:
It is very important that you keep the private key secret. Anyone with access to the private key can manage all the coins on the wallet. If an unauthorized person has access to the private key, he indicates that he is the owner of the wallet.
What is the cryptocurrency private key used for?
The private key is used to perform irreversible cryptocurrency transactions. It is the key to spending and sending cryptocurrency. The irreversibility is guaranteed by the signature associated with each transaction when the private key is used to send cryptocurrency.
The signature is unique for each transaction, even though they are generated with the same private key. This makes it impossible to copy or falsify transactions without the private key.