Blockchain is a new scequrity system.Almost every crypto coins depend on blockchain.It's work like a chain.This chains are used for batter scequrity.We know that in cryptocurrence there is no banking system.Without bank coin transection is difficult task.But blockchain made it easy. Blockchain is not only for cryptocurrence but also for any instrution.Because it can save your information and noone can hack it .It is very complicated for hackers.Here also added p2p system .For that when you transection any coin in that time you will get a code and other one also get a code.When hacker wants to hack it code will be changed automaticly. ***

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Now let's know the history of blockchain.

The concept of blockchain was came in 1991.But it was not a full concept.Then in 2008 a person name is Satoshi Nakamoto created blockchain .But Idon't know was he a person or a group of people.Anyway afterthat it was used on bitcoin .Now bitcoin is so strong system.It is strong for blockchain.The implementation of the blockchain within bitcoin made it the first digital currency to solve the double-spending problem without the need of a trusted authority or central server.

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Steemit also depend on blockchain .For every account user has 4 key.If you lost it then you not able to login your account. So these are very important and also save your account from hacker. In the next part I will discuss about bitcoin and blockchain system. It was today's post. Thanks for reading.

Bye!