51% attack

Hello all
Today I have come with a teaching blog.
Most of the traders to paid course for learning trade. There is a thing 51% attack. My today's blog is about 51% attack.

What is a 51% Attack?

A 51% attack is a type of attack occurred on Blockchain that performed by a
malicious miners group having control on 51% or more of the network's mining
hash rate.
What 51% Attackers can do?
After getting the majority of the hash rate attackers group get power to decide
which transactions are verified from the pool of unconfirmed transactions.
They have the ability to reverse the transactions which were occurred during
they own the majority of hash rate which is also known as a double-spending
attack.
There is also a probability that they can control the network completely by
preventing other miners to mine as well as can block all the transactions from
being confirmed on the network.

Source

What 51% Attackers can't do?

The group with the majority of the hash rate would not able to change the
consensus rules. They could not change block reward and even not able to reverse
the transactions of other users.They would not able to change the previous transactions data and had no power to
create new coins out of thin air.

How does a 51% Attack Work?

When Bitcoin users declared their signed bitcoin transactions on the bitcoin
network then these transactions will be added to the pool of unconfirmed
transactions.
Now miners select the transactions from this pool to verify these unconfirmed
transactions which are contained into a block of transactions together.
Miners need to find the solution of the very difficult mathematical problem which
required high computational power (known as a hash rate) in order to add this
block of transactions into the blockchain.
For miners having more computational power have a higher chance of finding the
solution of the problem before other miners find theirs in order to add the new
block into the Blockchain.
After finding the solution, miner broadcast the new block of transactions on the
network where all other miners will check the validity of the block on the basis of
the existing blockchain.
So, for miner having majority of hash rate (more computational power) can
easily add new block of its own transactions as well as can prevent other
miners from mining new blocks (due to low computation power they can't
even find the solution to the problem before him) which leads the 51% attack
on the blockchain.

Thanks for reading my blog.