In bitcoin, cryptography is used to come up with a key pair which manipulates access to the bitcoin present on the blockchain. The key pair for every bitcoin is made up of a public and private key. In this article, you will get to know more about bitcoin keys.
For starters, it would help to have some background understand about the bitcoin private key. A bitcoin private key is made up of 256 bits. This secret number is responsible for the unlocking and sending of the bitcoin. Every private key is made to create a unique signature. The signature ensures that the transactions are only done by the legit bitcoin owner. It is called a private key because it should be only known by the relevant person, it is secretive.
This is not the same with the bitcoin public key. Well, one similarity is that it is a huge number. However, it authorizes for the locking and accepting of the bitcoin. It get its name from the fact that it is meant for public sharing. It is built to permit receiving of funds.
To many, the draw line between a bitcoin private and public key is still a foreign concept. There have been explanations to draw out the differences, but they have ended up making them harder. The fact is, knowledge on digital signatures, signing transactions and wallet formats will not help a typical user in any way. It is possible for them to know more about keys in bitcoin in understandable explanations easily.
For better understanding, picture the public key cryptography as a lock. But take note; the lock has two keys instead of one. A, B and C are the specific points on the lock. When the key moves from B to A, it represents lock and receive, which is a public key. On the other hand, it is a private key if it moves from point B to C, which represents unlocking and sending. This explanation makes trusting the system easier..
Other than the differences between the two keys, they also relate. The relationship comes about mathematically on the secp256k1elliptic curve. Since the private key is randomly generated on the curve; the public key is the corresponding number on the curve.
It will also help if you know how bitcoin addresses and keys are made. Your bitcoin wallet software generates wallet file, addresses, and keys. The private key is generated from a section of the same software, which can accommodate many numbers. The section also randomly generates these numbers. There are millions and millions of private keys. Using the fact that there are huge numbers, the security is based on the fact that no one can generate the same private key in different instances.