Block header

There are six sections in the block's head:

The version number of the software
The hash of the previous block
The root hash of the Merkle tree
The time in seconds since 1970–01–01 T00: 00 UTC
The goal of the current difficulty
The nonce

The Version Number of the Software

Most of the time, it is irrelevant what software version you are using. A miner with a specific version number, however, can indicate which protocol choices he supports.

The Hash of the Previous Block

The previous block hash, figuratively speaking, is a chain of blockchains. Because the previous block hash is contained in the new block hash, the blockchain blocks are all intertwined. Without this component, there would be no communication and chronology between each block.

The Root Hash of the Merkle Tree

All transactions contained in the block can be combined with a hash. The Merkle tree starts here at its base.

The Time in Seconds Since 1970–01–01 T00: 00 UTC

A timestamp in the block itself. The time is given in seconds since 1.1.1970.

The Goal of the Current Difficulty

The objective specifies how tiny the new hash must be to be considered legitimate. Simply said, each hash has a size in bits. Finding a matching hash becomes more challenging as the goal's bit value decreases. A hash that starts out with a lot of zeros is smaller than one that doesn't.

The Nonce

A nonce is a variable that is amplified by proof of work. In this way, the miner predicts a valid hash, a hash smaller than the target.
Six sections form the header of the block. The blockchain title plays an important role in Bitcoin because it connects all the blocks together. You can think of it as a truck driver's place. Here are some of the important paperwork that a truck brings with it.

Block Body

The body of the block can be thought of as a loading truck. Contains all block transactions guaranteed by block. When a miner builds a block, it ensures a transaction. That is, you check that the sender has enough money to spend. He can easily read this information in a blockchain. The miner looks through the previous blocks to see if the sender has already received ten Bitcoins and if he wants to send ten Bitcoins. The blockchain transaction is not just on the list, but in the so-called Merkle Tree.

What is a Merkle Tree?

The Merkle Tree takes its name from mathematician Ralph Merkle. The finding was that more information could be represented in a single hash. With this, the data itself begins to accelerate. The hashes are then accelerated and reassembled. Finally, the Merkle Tree is combined into a single hash. The root hash, or last hash, refers to the tree's root. It represents all the information of its "leaves" (individual sales) and "branches" (leaf hashes) with relatively short cords.

Creating a root hash is quick and easy, as long as all the branches and leaves are known. We remember the hash function: it works clearly and quickly on one side and it is impossible to break down on the other side. If the root hash is known, but the transaction is unknown, it is not possible to guess the transaction.

So the root hash alone is not enough, and every part of the block should be kept. Therefore, the miner can verify the root hash at any time by speeding up the information contained in the block as well. As long as the hash function is the same, miners always get the same hash for the input given data. This is very useful because they can only check that they are at the same level as the hash.

Mining: The Search for a Special Hash

In this context, it is easy to understand the excavation of work evidence. When mining, the head of the block is continuously changed to get a special hash. The title contains five fixed elements and one variation. Constants software version number, previous block hash, Merkle tree root hash, timestamp, and targeted bit hash search. The variable is nonce. A nonce is a number suggested by another. The miner then speeds up the data and checks that the data results in a hash below the targeted search value. If the hash value is greater than the target, the miner repeats the process; So it increases each nonce, hashes, and checks again. Repeats this until it finds the hash below the target, or finds another block in another network with the hash below the target. Then take this new block and use it as the basis for the next block (using the new hash as the "previous block hash").
Mining is a very repetitive process whose purpose is to obtain a special hash. Once the hash is detected, the game resumes. The chances of getting a special hash depending on the difficulty. On average Bitcoin gets a new block every ten minutes. The difficulty remains flexible, so this ratio remains the same.
A special feature of this process is that a special hash can only be obtained by guessing. This level costs computer computing as well as power. Looking at a special hash is enough to see that it is special because it starts with zero.

Here is an example of such a hash from the Bitcoin blockchain:

000000000000000000094bfa4edb1245c347e42452e4418e9fe5a1d24e335b16