Introduction
In this tutorial, you’ll learn the Hash function and Hash Block, and for this Hash function. using the following Hash generator link you can check Hash value.
The cryptographic Hash is basically a digest, or a digital fingerprint, of a certain amount of data. that means It is an amount of data alphanumerically in a certain length.
If You enter every single character, as we build it out, you have a cryptographic Hash equivalent and then we get SHA 256 Hash text.
The SHA256 bit stands for Secure Hash Algorithm. and the SHA 256 hash algorithm was developed by the NSA, the National Security Agency, and this entire program is a hash generator.
SHA 256 is the type of hash function that is used in Bitcoin. it allows you to do is that you will always be able to generate a hash from a certain amount of data.
But, there is no way whats and whoever to go back to the original text. In other words, there is no way for you to get this entire text from this one Hash Function.
This is different from encryption. when you encrypt something you can, using the right secret key, decrypt that message and retrieve the original.
But with a hash, you do not. A hash generates a unique fingerprint that cannot be reversed back to the original amount. It is a one way directional.
Block Hashes
Now, you’re familiar with the concept of cryptographic hash function and we already discuss SHA256. and step by step we’ll see how it applies to build a block within a blockchain. And we’re going to be talking specifically, in the context of the Bitcoin blockchain so you understand how this ties into the role of the miners.
So, the miners are actually building blocks. and these blocks add to a blockchain to build out what the Bitcoin blockchain will be.
The first block is composed of a block number and the third field Nonce, it has a cryptographic hash associated with it, and the third field has called data.
In the hash field, These four leading zeros it describes, when a block is valid or not. So, if you make any change in the data field, for example, by adding a single character, then you get a completely different hash.
A cryptographic hash is basically a digest of whatever information you’re compressing into that one hash. So when we do a cryptographic hash for this block. including this extra character of an in it, you’re getting a completely different cryptographic hash. And this one no longer has four leading zeroes.
So, another field is Nonce, it stands for a Number Used Once. and it’s basically a random number that uses for figuring out how you can actually make this specific block give you a valid hash.
The nonce that will give you a hash that will have those four zeroes at the beginning. And we found it, it would be seventy-one thousand eight hundred fifty.
Now, so one interesting thing about this whole process is that if you were to change anything in this. for example, try a different block number, you would have a completely different cryptographic hash.
So, it would not work you always would have to get this combination to be able to get those four leading zeroes. and if you did any changes to it you would again get a completely different cryptographic hash. And the block would no longer be valid.
Actually, the whole concept of how cryptography ties into assembling a block and making sure that a block is valid within a blockchain.
