The blockchain is the technology the underpins digital currency (Bitcoin, Litecoin, Ethereum, and the like). The tech allows digital information to be distributed, but not copied. ... You may hear it described as a “digital ledger” stored in a distributed network.

1. Made by:-Suman nayak

3.  Blockchain is a type of distributed ledger for
maintaining a permanent and tamper-proof record
of transactional data. A blockchain functions as a
decentralized database that is managed by computers
belonging to a peer-to-peer (P2P) network. Each of the
computers in the distributed network maintains a
copy of the ledger to prevent a single point of failure
(SPOF) and all copies are updated and validated
simultaneously.

4.  Blockchain was invented by Satoshi Nakamoto in 2008
to serve as the public transaction ledger of
the cryptocurrency bitcoin.[1] The invention of the
blockchain for bitcoin made it the first digital currency
to solve the double-spending problem without the
need of a trusted authority or central server. The
bitcoin design has inspired other applications

5.  blockchain technology can be integrated into multiple
areas. The primary use of blockchains today is as a
distributed ledger for cryptocurrencies, most notably
bitcoin.[70] While a few central banks, in countries and
regions such as India, China, Hong Kong, United
States, Sweden, Singapore, South Africa and
the United Kingdom are studying issuance of a Central
Bank Issued Cryptocurrency (CICC), none have done
so as of 22 December 2016

6.  General potentials
Blockchain technology has a large potential to
transform business operating models in the long term.
Blockchain distributed ledger technology is more
a foundational technology—with the potential to
create new foundations for global economic and social
systems—than a disruptive technology, which typically
"attack a traditional business model with a lower-cost
solution and overtake incumbent firms quickly

7.  Frameworks and trials such as the one at the Sweden
Land Registry aim to demonstrate the effectiveness of
the blockchain at speeding land sale deals.The
Republic of Georgia is piloting a blockchain-based
property registry The Government of India is fighting
land fraud with the help of a blockchain . Andhra
Pradesh became the first state in India to adopt
blockchain technology in government. To do so it was
announced about setting up blockchain Technology
Park in Visakhapatnam, which to be supported by
blockchain technology companies Apla.

8. Each of the Big Four accounting firms is testing blockchain
technologies in various formats. Ernst & Young has
provided cryptocurrency wallets to all (Swiss)
employees, has installed a bitcoin ATM in their office in
Switzerland, and accepts bitcoin as payment for all its
consulting services. Marcel Stalder, CEO of Ernst & Young
Switzerland, stated, "We don't only want to talk about
digitalization, but also actively drive this process together
with our employees and our clients. It is important to us
that everybody gets on board and prepares themselves for
the revolution set to take place in the business world
through blockchains, to smart contracts and digital
currencies.

9. Blockchain-based smart contracts are contracts that can
be partially or fully executed or enforced without
human interaction. One of the main objectives of a
smart contract is automated escrow. The IMF believes
smart contracts based on blockchain technology could
reduce moral hazards and optimize the use of
contracts in general. Due to the lack of widespread use
their legal status is unclear

10.  Level One Project from the Bill & Melinda Gates
Foundation aims to use blockchain technology to help
the two billion people worldwide who lack bank
accounts.
 Building Blocks project from the U.N.'s World Food
Programme (WFP) aims to make WFP's growing cash-
based transfer operations faster, cheaper, and more
secure. Building Blocks commenced field pilots in
Pakistan in January 2017 that will continue throughout
spring.

12. The director of the Office of IT Schedule Contract
Operations at the US General Services Administration, Jose
Arrieta, disclosed at the September 2017 ACT-IAC
(American Council for Technology and Industry Advisory
Council) Forum that its organization is using blockchain
distributed ledger technology to speed up the FAST Lane
process for IT Schedule 70 contracts through automation.
Two companies, United Solutions (prime contractor) and
Sapient Consulting (subcontractor) are developing for
FAST Lane a prototype to automate and shorten the time
required to perform the contract review process.
The Commercial Customs Operations Advisory Committee,
a subcommittee of the U.S. Customs and Border
Protection, is working on finding practical ways Blockchain
could be implemented in its duties.

13. Don Tapscott conducted a two-year research project
exploring how blockchain technology can securely move
and store host "money, titles, deeds, music, art, scientific
discoveries, intellectual property, and even
votes". Furthermore, major portions of the financial
industry are implementing distributed ledgers for use
in banking, and according to a September 2016 IBM study,
this is occurring faster than expected.
Banks are interested in this technology because it has
potential to speed up back office settlement systems.
Banks such as UBS are opening new research labs dedicated
to blockchain technology in order to explore how
blockchain can be used in financial services to increase
efficiency and reduce costs

14. The credit and debits payments company MasterCard has
added three blockchain-based APIs for programmers to use
in developing both person-to-person (P2P) and business-
to-business (B2B) payment systems.CLS Group is using
blockchain technology to expand the number of currency
trade deals it can settle.
VISA payment systems, MasterCard ,Union pay and
SWIFT have announced the development and plans for
using blockchain technology.
Prime Shipping Foundation is using blockchain
technology to address issues related to payments in the
shipping industry, seeking 150 million USD to develop their
proprietary PRIME Token.

16. A public blockchain has absolutely no access
restrictions. Anyone with an internet connection can
send transactions to it as well as become
a validator (i.e., participate in the execution of
a consensus protocol).Usually, such networks
offer economic incentives for those who secure them
and utilize some type of a Proof of Stake or Proof of
Work algorithm.Some of the largest, most known
public blockchains are Bitcoin and Ethereum.

17. A private blockchain is permissioned. One cannot join
it unless invited by the network administrators.
Participant and validator access is restricted.
This type of blockchains can be considered a middle-
ground for companies that are interested in the
blockchain technology in general but are not
comfortable with a level of control offered by public
networks. Typically, they seek
to incorporate blockchain into their accounting and
record-keeping procedures without sacrificing
autonomy and running the risk of exposing sensitive
data to the public internet.

18. A consortium blockchain is often said to be semi-
decentralized. It, too, is permissioned but instead of a
single organization controlling it, a number of
companies might each operate a node on such a
network. The administrators of a consortium chain
restrict users’ reading rights as they see fit and only
allow a limited set of trusted nodes to execute a
consensus protocol.

20. The blockchain is an actual creative invention – the
brainchild of a person or group of people known by the
pseudonym, Satoshi Nakamoto. But since then, it has
evolved into something greater, and the main question
every single person is asking is: What is Blockchain
By allowing digital information to be distributed but
not copied, blockchain technology created the
backbone of a new type of internet. Originally devised
for the digital currency, Bitcoin, (Buy Bitcoin) the tech
community is now finding other potential uses for the
technology.

22. By allowing digital information to be
distributed but not copied, blockchain
technology created the backbone of a new
type of internet. Originally devised for
the digital currency, Bitcoin, (Buy Bitcoin) the
tech community is now finding other potential
uses for the technology. As revolutionary as it
sounds, Blockchain truly is a mechanism to
bring everyone to the highest degree of
accountability. No more missed transactions,
human or machine errors, or even an
exchange that was not done with the consent
of the parties involved. Above anything else

23.  The blockchain network lives in a state of consensus,
one that automatically checks in with itself every ten
minutes. Each group of these transactions is referred
to as a “block”. Two important properties result from
this:
 Transparency data is embedded within the network
as a whole, by definition it is public.
 It cannot be corrupted altering any unit of
information on the blockchain would mean using a
huge amount of computing power to override the
entire network.

25.  A network of so-called computing “nodes” make up
the blockchain.
 Node(computer connected to the blockchain network
using a client that performs the task of validating and
relaying transactions) gets a copy of the blockchain, which
gets downloaded automatically upon joining the
blockchain network.

27.  By design, the blockchain is a decentralized technology.
 Anything that happens on it is a function of the network as
a whole. Some important implications stem from this. By
creating a new way to verify transactions aspects of
traditional commerce could become unnecessary. A global
network of computers uses blockchain technology to
jointly manage the database that records Bitcoin
transactions. That is, Bitcoin is managed by its network,
and not any one central authority. Decentralization means
the network operates on a user-to-user (or peer-to-peer)
basis. The forms of mass collaboration this makes possible
are just beginning to be investigated.

31. The blockchain technology is based on decentralisation
which means the data is accessible to everyone while
the data is managed by a cluster of computers and not
owned by a single person.
One of the major issues with today’s digital economy is
online security. Blockchain addresses that concern to a
large extent.

32.  As stated in our guide "What is Blockchain
Technology?", there are three principal technologies
that combine to create a blockchain. None of them are
new. Rather, it is their orchestration and application
that is new.
 These technologies are: 1) private key cryptography, 2)
a distributed network with a shared ledger and 3) an
incentive to service the network's transactions, record-
keeping and security. The following is an explanation
of how these technologies work together to secure
digital relationships.

33. Cryptographic keys
Two people wish to transact over the internet.

34. Each of hold a private key and public key.

35.  The main purpose of this component of blockchain
technology is to create a secure digital identity
reference. Identity is based on possession of a
combination of private and public cryptographic keys.
 The combination of these keys can be seen as a
dexterous form of consent, creating an extremely
useful digital signature.
 In turn, this digital signature provides strong control
of ownership.

37. But strong control of ownership is not enough to secure
digital relationships. While authentication is solved, it
must be combined with a means of approving
transactions and permissions (authorisation).
For blockchains, this begins with a distributed
network.

38. The benefit and need for a distributed network can be
understood by the 'if a tree falls in the forest' thought
experiment Much of the value of the bitcoin
blockchain is that it is a large network where
valuators', like the cameras in the analogy, reach a
consensus that they witnessed the same thing at the
same time. Instead of cameras, they use mathematical
verification.
.

40. When cryptographic keys are combined with this
network, a super useful form of digital interactions
emerges. The process begins with A taking their
private key, making an announcement of some sort —
in the case of bitcoin, that you are sending a sum of the
cryptocurrency — and attach it to B's public key.

41. From :- Suman Nayak