What Is the Blockchain?

The blockchain is the public ledger of all Bitcoin transactions that have ever been exe‐cuted. It is constantly growing as miners add new blocks to it (every 10 minutes) to record the most recent transactions.

The blocks are added to the blockchain in a linear, chronological order. 

The blockchain as a public ledger means that it is easy to query any block explorer for transactions associated with a particular Bitcoin address—for example, you can look up your own wallet address to see the transaction in which you received your first Bitcoin.

The blockchain is seen as the main technological innovation of Bitcoin because   it stands as a “trustless” proof mechanism of all the transactions on the network.The blockchain as the architecture for a new system of decentralized trustless transactions is the key innovation. The blockchain allows the disintermediation and decentralization of all transactions of any type between all parties on a global basis.



The Connected World and Blockchain: The Fifth Disruptive

1.Computing Paradigm


First, there were the mainframe and PC (personal computer) paradigms, and then the Internet revolutionized everything. Mobile and social networking was the most recent paradigm. The current emerging paradigm for this decade could be the connected world of computing relying on blockchain cryptography. 

Apple Pay (Apple’s token-based ewallet mobile app) and its competitors could be a critical intermediary step in moving to a full-fledged cryptocurrency world in which the blockchain becomes the seamless economic layer of the Web.



Technology Stack: Blockchain, Protocol, Currency


Bitcoin terminology can be confusing because the word Bitcoin is used to simultane‐ously denote three different things. First, Bitcoin refers to the underlying blockchain technology platform. Second, Bitcoin is used to mean the protocol that runs over the underlying blockchain technology to describe how assets are transferred on the blockchain. Third, Bitcoin denotes a digital currency, Bitcoin, the first and largest of

the cryptocurrencies.

1.How work cryptocurrency? 

(i) Bitcoin is money, digital cash, a way of buying and selling things over the Internet.

(ii) The Bitcoin value chain is composed of several different constituencies: software

developers, miners, exchanges, merchant processing services, web wallet companies,

and users/consumers. 

(iii) From an individual user’s perspective, the important elements in transacting coin (I’ll use “coin” in the generic sense here) are an address, a private key, and wallet software. 



2.Merchant Acceptance of Bitcoin


(i) At the time of writing, the main Bitcoin merchant processing solutions for vendors to accept Bitcoin are BitPay and Coinbase in the United States, and Coinify in Europe.

However, it is difficult for vendors, like the local café, to run two separate payment

systems (traditional and Bitcoin), so a more expedient future solution would involve

integrating Bitcoin payment into existing vendor payment networks. Mobile payment

functionality is also needed for quick point-of-sale Bitcoin purchases (for example, a

cup of coffee) via mobile phone.



3.The Blockchain Is an Information Technology


Perhaps most centrally, the blockchain is an information technology. But blockchain technology is also many other things. The blockchain as decentralization is a revolu‐

tionary new computing paradigm. The blockchain is the embedded economic layer the Web never had. The blockchain is the coordination mechanism, the line-item attribution, credit, proof, and compensation rewards tracking schema to encourage

trustless participation by any intelligent agent in any collaboration. The blockchain

“is a decentralized trust network.”


4.Blockchain AI: 

Consensus as the Mechanism to Foster “Friendly” AI one forward-looking but important concern in the general future of technology is

different ways in which artificial intelligence (AI) might arise and how to sponsor it

such that it engenders a “friendly” or benevolent relationship with humans. 


5.Large Possibility Space for Intelligence


Speculatively looking toward the longer term, there might be a large possibility space of intelligence that includes humans, enhanced humans, different forms of human/machine hybrids, digital mindfile uploads, and different forms of artificial intelli‐gence like simulated brains and advanced machine learning algorithms.