What is the Blockchain

I make no apology for this being very much a 101 level blog but I assume there still many like me who are still trying to get their heads around this latest technology and have their heads full of various terms which they have yet to fully understand.

From my perspective I like to at least understand the basics and it strikes me that the Blockchain is the one to get to grips with , given that it is most likely to be adopted universally by many industries whether it is for financial purposes or supply chain logistics. I've obviously had to find a suitable source and so have chose one from https://cointelegram.com (thanks Tom for listing all those channels on Telegram for "sloths"  like me to tune into)   

In simple terms a blockchain is a "dairy that is almost impossible to copy"

This is because a program called a hash function is used. 

A Hash is  string of numbers and letters and is a mathmatical function that takes a variable number of characters and converts it into a string with a fixed number of characters.

# Transactions are entered in the order in which they occur. Order is very importsnt. Even a a small change in a string creates a new hash.   

# A database entry that records tractional information results in the creation of  a hash.

#The hash depends not only on the transaction but also on the previous transaction's hash

#Even the smallest of changes produces a has that has no similarity to the original.

For example :

Ann gives 10 coins to Mary. Hash: cff4e860bd57c2bfb7c010927c3f6fee

Mary gave 5 coins to Jack. Hash: 803c28370e9a16e628a23d46d3ebe711

If Jack decides to change the records (to give himself more money);

Mary gave 8 coins to Jack

the resulting hash would be : 4ae41f8cc3d4cc905f664c75ceab9dao

To make it  impossible to forge a record, various technics are applied to each hash record that make any unauthorised changes to be effectve impossible, because of the distributed nature of the database, and the need for the forger to alter every assocated record in every node of the network. One such technic is called a "nonce" (00 added to the end of every record), makes it impossible for even computers to figure out quickly

These computers are called Nodes  and each node has a copy of the digital ledger or "Blockchain" and each transaction must be approved by each Node in the blockchain. Once each node has check the transaction (some will agree and some will disagree as to its validity) there a "sort of an electronic vote" to decide.

A very  important point to note is that one spreadsheet (of a fixed size) is a block and a family of blocks is a blockchain which updates itself across all nodes every tem minutes AUTOMATICALLY. There is NO Master or Central computer that instructs the computers (ie the Nodes) to do this . When that node involves literally millions of computers spread across the world the ability to resist interference and attempts to take over is extremely powerful. Hence the resistence from the Command and Control lobby to this type of technology.   

Hopefully this is only part one of my BlockChain voyage of discovery . 

Have You Learnt To Elevate Your Life Yet