What is Blockchain Technology?

Blockchains can be describe as an incorruptible ledger used to store information, at its core it works just like the traditional ledger that has been used for centuries for recording the relationship between credit and debit.
Blockchain is a publicly distributed encrypted database holding encrypted ledgers.
Blockchain technology was created to attempt to solve the problem of money transfer and to create a more secure and cheaper way of storing value.
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Traditionally when money is being transferred between parties it is typically done via a conduit, for example, if A wants to transfer money to B he/she does this via a trusted third party, so, A lodges the money with the third party, (typically some sort of financial institution) the third party then transfers the money to B having taken a commission, this process typically takes approximately three working days.

Blockchain technology has evolved this process, made it simpler and made it cheaper, with blockchain technology the money / value can be transferred directly from A to B without the need for a third party, with virtually no fees and the transaction can be completed within minutes.
Blockchain technology has developed a system called open ledger, open ledger enables all of the parties in a transaction to view all of the chains of that transaction, so, with an open ledger if A initially has a $100 and transfers 50 to B, the 100 is visible on the open ledger as is the 50 that was transferred and to whom and the balance of 50 that is left is also visible, this is how the open ledger works.

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this system is aided by a process of encryptions and verification, when A initiates a transfer to B an encrypted signal of this intention is sent to the blockchain network, the blockchain network is full of miners (nodes), these miners are computers plugged into the blockchain (these computers are individually own and are spread worldwide, anybody with a powerful enough computer can plug into the blockchain and mine cryptocurrencies), the miners check and verify the transaction, (they check if A has the money that he is about to send, that B has the proper receiving address, that A is not double spending, that the value being transferred is deducted from A and credited to B, that the new balance of both A and B are properly recorded and stored, etc.) once the transaction has been validated, it is then stored on the blockchain for record purposes.
The miners are in a race to verify transactions, whichever miner verifies a transaction first gets rewarded with a fraction of the crytpcurrency in question, this process is called “mining”. Once the transaction has been verified copies of it are stored individually on all of the computers plugged into the network, this is called a distributed open ledger.

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The distributed open ledger is one of the key components that makes cryptocurrencies secure, copies of verified transactions are individually stored on the node of miners’ computers right across the network with copies of validated transactions individually kept on mining computers worldwide this makes the system virtually impenetrable.
Future transactions on validated transactions are checked against records kept in a repeat of the process described above.
In summary a blockchain is a series of nodes and miners that are used to verify, validate, transfer and store value.