Blockchain Facts_What Is It, How IT Works and How Can It Be Used.pdf

Blockchain Facts:What Is It, How IT
Works and How Can It Be Used
What Is a Blockchain?
A blockchain is a shared distributed database or ledger between computer network nodes. A
blockchain serves as an electronic database for storing data in digital form. The most
well-known use of blockchain technology is for preserving a secure and decentralised record
of transactions in cryptocurrency systems like Bitcoin. The innovation of a blockchain is that
it fosters confidence without the necessity for a reliable third party by ensuring the fidelity
and security of a record of data.
The way the data is organised in a blockchain differs significantly from how it is typically
organised. In a blockchain, data is gathered in groups called blocks that each include sets of
data. Blocks have specific storage capabilities, and when filled, they are sealed and
connected to the block that came before them to create the data chain known as the
blockchain. Every additional piece of information that comes after that newly added block is
combined into a brand-new block, which is then added to the chain once it is full.
A blockchain, as its name suggests, arranges its data into pieces (blocks) that are strung
together, whereas a database typically organises its data into tables. When used in a
decentralised way, this data structure creates an irreversible chronology of data by design.

When a block is completed, it is irrevocably sealed and added to the timeline. When a block
is added to the chain, it receives a precise timestamp.
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KEY TAKEAWAYS
● A blockchain is a particular kind of shared database that varies from other databases
in that it saves data in blocks that are subsequently connected via cryptography.
● A new block is created as each new piece of data arrives. The data is chained
together in chronological sequence once the block has been filled with information
and is attached to the block before it.
● Although other kinds of information can be maintained on a blockchain, a transaction
ledger has so far been its most popular use.
● Blockchain is utilised in the context of Bitcoin in a decentralised manner, ensuring
that no one user or organisation has power but rather that all users collectively
maintain control.
● Since decentralised blockchains are immutable, the data entered into them cannot be
changed. This implies that transactions made using Bitcoin are publicly visible and
permanently recorded.
How Does a Blockchain Work?
Blockchain aims to make it possible to share and record digital information without editing it.
A blockchain serves as the basis for immutable ledgers, or records of transactions that
cannot be changed, removed, or destroyed. Blockchains are also referred to as distributed
ledger technologies because of this (DLT).
The blockchain idea was first put forth as a research project in 1991, long before Bitcoin
became a widely used application in 2009. Since then, the introduction of numerous
cryptocurrencies, decentralised finance (DeFi) applications, non-fungible tokens (NFTs), and
smart contracts has led to an explosive growth in the use of blockchains.

Transaction Process
Attributes of Cryptocurrency

Blockchain Decentralization
Consider a business with a server farm of 10,000 machines that it uses to keep a database
with all of its clients' account information. All of these computers are located in a warehouse
that belongs to this corporation, and it has complete authority over each of them as well as
the data they hold. But this creates a single point of failure. What would happen if the
electricity at that place failed? What if the computer's Internet connection is lost? What if it
completely burns down? What happens if a malicious person deletes everything with a
single keypress? The information is either missing or damaged.
What a blockchain does is enable the distribution of the data stored in that database across
multiple network nodes located in different places. This not only adds redundancy but also
preserves the accuracy of the data stored there; for example, if someone tries to change a
record at one database instance, the other nodes won't be changed, preventing a bad actor
from doing so. All other nodes would cross-reference one another and be able to quickly
identify the individual who tampered with Bitcoin's transaction history. This approach aids in
creating a clear and precise sequence of events. This prevents any one node in the network
from changing the data it contains.
As a result, the data and history (such as those of cryptocurrency transactions) are
irreversible. A blockchain may store a variety of data, including legal contracts, state
identifications, or a company's goods inventory. Such a record may be a list of transactions
(such as with a cryptocurrency).
Important:A majority of the decentralised network's computer power would need to concur
in order to validate new records or entries to a block. Blockchains are safeguarded by a
consensus technique like proof of work (PoW) or proof of stake to stop malicious parties
from confirming incorrect transactions or multiple spends (PoS). Even in cases when no
single node is in charge, these procedures still enable consensus.
Transparency
Due to the decentralised structure of the Bitcoin blockchain, all transactions may be
transparently observed by utilising blockchain explorers, which enable anybody to examine
transactions as they happen in real time, or by owning a personal node. As new blocks are
added and confirmed, each node's copy of the chain is updated. This implies that you might
follow Bitcoin wherever it went if you so desired.
As an illustration, exchanges have previously been hacked, and anyone who had Bitcoin
stored there lost everything. The stolen Bitcoins are clearly identifiable, despite the hacker's
complete anonymity. It would be known if any of the Bitcoins taken in some of these hacks
were transferred or used elsewhere.

Naturally, the data kept on the Bitcoin blockchain (as well as the majority of others) is
encrypted. This implies that only the record's owner will be able to decode the file and
expose their identity (using a public-private key pair). As a result, blockchain users can
maintain their anonymity while maintaining transparency.
Is Blockchain Secure?
Decentralised security and trust are made possible by blockchain technology in a number of
ways. To start, new blocks are always chronologically and linearly stored. In other words,
they are constantly added to the blockchain's "end." It is very difficult to go back and change
the contents of a block once it has been added to the blockchain unless a majority of the
network has agreed to do so. This is due to the fact that each block has its own hash, as well
as the hash of the block that came before it and the aforementioned date.A mathematical
function that converts digital information into a string of numbers and letters produces hash
codes. The hash code also changes if that data is altered in any way.
Imagine a hacker who also manages a node on a blockchain network wants to change a
blockchain and take everyone else's cryptocurrency. If they changed their own copy, it
wouldn't match the copies made by everyone else. When everyone compares their copies to
one another, they will notice that this one copy stands out, and the hacker's version of the
chain will be rejected as fraudulent.
For such a hack to be successful, the hacker would need to simultaneously control and
change at least 51% of the blockchain copies, making their new copy the majority copy and,
thus, the agreed-upon chain. The requirement to rewrite every block because their
timestamps and hash codes had changed would make such an attack extremely expensive
and resource-intensive.
The expense to pull off such a feat would probably be impossible due to the size of many
cryptocurrency networks and how quickly they are developing. Not only would this be very
expensive, but it would probably be useless. As network participants would observe such
significant changes to the blockchain, doing such a thing would not go unnoticed. The
network's users would then abruptly switch to an unaffected version of the chain. As a result,
the token version that was attacked would lose value, rendering the attack ultimately useless
because the malicious party would then be in control of a worthless asset.The same thing
would happen if the malicious party targeted Bitcoin's most recent fork. As a result,
participating in the network is much more economically advantageous than assaulting it.

Bitcoin vs. Blockchain
Stuart Haber and W. Scott Stornetta, two researchers interested in implementing a system
where document timestamps could not be altered, first proposed the concept of blockchain
technology in 1991. But blockchain didn't have its first practical use until over two decades
later, with the introduction of Bitcoin in January 2009.
On a blockchain, the Bitcoin protocol is constructed. Bitcoin's anonymous founder, Satoshi
Nakamoto, described the digital currency as "a new electronic cash system that's totally
peer-to-peer, with no trusted third party" in a research paper introducing it.
It's important to note that blockchain is only utilised by Bitcoin to immutably record a ledger
of payments in a transparent manner. In theory, though, blockchain could be used to
immutably record any number of data points. This could take the shape of transactions,
votes in elections, goods inventories, state identifications, deeds to properties, and much
more, as was previously said.
In addition to recording transactions, tens of thousands of projects are currently working to
utilise blockchain technology in a number of other ways to benefit society. One such
application is a secure voting system for democratic elections. The immutability of
blockchain technology makes it much more difficult to conduct fraudulent voting. For
instance, a voting process might be designed so that each nation's citizen receives a single
coin or token. The voters would then deposit their token or cryptocurrency to the address of
whatever candidate they wish to support. Each candidate would then be granted a unique
wallet address.Blockchain's transparency and traceability would do away with the necessity
for manual vote counting as well as criminals' capacity to tamper with actual votes.
Blockchain vs. Banks
Blockchain technology has been hailed as a disruptive force for the financial industry,
particularly for the payment and banking processes. Banks and decentralised blockchains,
however, are very dissimilar.
Let's contrast the banking system with Bitcoin's implementation of blockchain to discover
how it differs from a bank.

How Are Blockchains Used?
As we now understand, blocks on the blockchain of Bitcoin store information about monetary
transactions. More than 10,000 additional cryptocurrency systems are currently active on the
blockchain. However, it transpires that using a blockchain to store information about other
kinds of transactions is also a secure method.
Walmart, Pfizer, AIG, Siemens, Unilever, and numerous more businesses are just a few that
have already adopted blockchain technology. For instance, IBM developed the Food Trust
blockchain to track food goods' routes to their destinations.
Why do this? The food sector has had numerous E. coli, salmonella, and listeria outbreaks
as well as the unintentional contamination of goods with dangerous substances. Finding the
origin of these outbreaks or the illness that results from what people consume has in the
past taken weeks. Brands may follow a food product's journey using blockchain, from its
origin through each stage along the way to its delivery. Food contamination can be tracked
back through all of the stops until it reaches its original location.Additionally, because these
businesses can now see everything else they may have come into contact with, problems
can be identified far earlier, potentially saving lives. Although there are other more ways to
implement blockchain, this is only one example.
Banking and Finance
Banking is one sector that might stand to gain the most from incorporating blockchain into its
corporate operations. Financial institutions are only open during regular business hours,
which are typically five days per week. As a result, if you attempt to deposit a check on
Friday at 6pm, you probably won't see the funds in your account until Monday morning. Due
to the enormous volume of transactions that banks must settle, even if you do make your
deposit within business hours, it may still take one to three days for the transaction to be
verified. Blockchain, however, is always active.
Customers may expect their transactions to be processed by banks using blockchain in as
little as 10 minutes—basically the time it takes to add a block to the blockchain, regardless of
the day of the week or holidays. Banks now have the ability to securely and swiftly transfer
money between organizations thanks to blockchain technology. For instance, in the stock
trading industry, the settlement and clearing process may take up to three days (or longer, if
trading is done worldwide), during which time the money and shares are frozen.

Given the scale of the amounts involved, even a little period of time during which the money
is in transit can be extremely expensive and risky for banks.
Currency
For cryptocurrencies like Bitcoin, blockchain serves as the foundation. The Federal Reserve
is in charge of the US dollar. A user's data and money are technically subject to the whims of
their bank or government under this system of central power. The private information of a
client is in danger if their bank is hacked. The value of the client's money may be in jeopardy
if their bank fails or if they reside in a nation with a volatile government. A number of failing
banks were partially bailed out in 2008 with taxpayer funds. These are the concerns that led
to the initial conception and development of Bitcoin.
Blockchain enables Bitcoin and other cryptocurrencies to function decentralised by
dispersing its activities across a network of computers. In addition to lowering risk, this also
does away with numerous processing and transaction expenses. Additionally, it can provide
people in nations with weak financial systems or currencies with a more stable currency that
has a wider range of uses and a larger network of contacts with whom they can do business
both locally and abroad.
For those without state identity, using cryptocurrency wallets as savings accounts or
payment methods has a particularly significant impact. Some nations can be in a state of
civil conflict or have weak administrations with no meaningful infrastructure for issuing
identity. These nations' citizens might not have access to savings or brokerage accounts,
leaving them without a secure place to keep their money.
Healthcare
Healthcare providers can use blockchain to safely preserve the medical records of their
patients. The ability to write a medical record onto the blockchain once it has been created
and signed gives patients the assurance that the record cannot be altered. These sensitive
health records might be encrypted and kept on the blockchain with a secret key so that only
specific people can access them, maintaining their privacy.

Property Records
If you've ever spent time in your local recorder's office, you are aware of how
time-consuming and ineffective the process of documenting property rights is. A tangible
deed must now be handed to a government worker at the county recording office, where it
will be manually put into the public index and central database. Claims to the property that
are in dispute must be compared to the public index.
This method is not only expensive and time-consuming, but it is also prone to human error,
where each error reduces the effectiveness of tracking property ownership. Blockchain might
do away with the requirement to scan documents and locate actual files in a nearby
recording office. Owners can have confidence that their deed is correct and permanently
recorded if property ownership information is kept and verified on the blockchain.
It can be very difficult to establish ownership of a property in war-torn nations or regions with
little to no financial or governmental infrastructure. It is especially difficult in places without a
Recorder's Office. A group of locals might build transparent and unambiguous time lines of
property ownership if they were able to use blockchain.
Smart Contracts
A contract agreement can be facilitated, verified, or negotiated using a smart contract, which
is computer code that can be included into the blockchain. Users accept a set of terms under
which smart contracts operate. The terms of the Agreement shall automatically be carried
out upon the satisfaction of such requirements.
Let's take the example of a prospective tenant who wants to rent an apartment through a
smart contract. When the tenant pays the security deposit, the landlord agrees to give the
tenant the apartment's door code. The smart contract would receive payments from both the
renter and the landlord, keep them, and then automatically exchange the door code for the
security deposit on the start date of the lease. The smart contract returns the security
deposit if the landlord does not provide the door code by the start of the lease. This would do
away with the costs and procedures usually related to using a notary, a third-party mediator,
or lawyers.

Supply Chains
Suppliers can utilise blockchain to track the sources of the materials they have purchased,
similar to the IBM Food Trust example. This would enable businesses to confirm the
legitimacy of both their own products and well-known labels like "Organic," "Local," and "Fair
Trade."
According to Forbes, the food sector is utilising blockchain technology more and more to
track the whereabouts and safety of food as it travels from the farm to the consumer.
Voting
As was already suggested, a modern voting system might be facilitated by blockchain. As
demonstrated in the West Virginia midterm elections in November 2018, voting using
blockchain technology has the ability to end election fraud and increase voter turnout.
5
With the use of blockchain, tampering with votes would be next to impossible. The
blockchain protocol will also uphold electoral openness while lowering the number of people
required to carry out an election and giving officials access to results almost immediately. As
a result, there would be no need for recounts and no legitimate reason to be concerned that
election fraud would occur.
Pros and Cons of Blockchain
Despite its intricacy, blockchain has virtually limitless potential as a decentralised method of
record-keeping. Blockchain technology may very possibly find applications beyond those
mentioned above, ranging from improved user privacy and security to reduced processing
costs and fewer mistakes. But there are some drawbacks as well.
Pros
● increased accuracy due to the absence of human verification
●
● Cost savings through the abolition of third-party verification
●
● Decentralisation makes it more difficult to interfere
●
● The transactions are efficient, confidential, and safe.
●
● Open-source technology
●
● Gives residents of nations with unstable or weak governments a financial alternative
and a way to secure their personal information.

Cons
● Bitcoin mining has a high technological cost.
●
● low transactional speeds
●
● Use in illegal operations in the past, such as on the dark web
●
● Regulation differs between jurisdictions and is still ambiguous.
●
● storage restrictions for data
Benefits of Blockchains
Accuracy of the Chain
A network of thousands of computers approves transactions on the blockchain network. As a
result, practically all human involvement in the verification process is eliminated, which
reduces human error and ensures that the information is recorded accurately. Even if one of
the computers in the network were to make a computational error, only one copy of the
blockchain would be affected. It would take at least 51% of the network's computers making
that mistake for it to spread to the rest of the blockchain, which is nearly impossible for a
network as big and expanding as Bitcoin's.
Cost Reductions
Consumers typically pay a bank to confirm a transaction, a notary to sign a document, or a
preacher to officiate a wedding. Third-party verification is no longer required, and with it, its
accompanying costs. For instance, minor fees are charged to business owners who accept
credit card payments since banks and payment processors must handle those transactions.
Contrarily, Bitcoin lacks a central authority and has a small number of transaction fees.
Decentralisation
Blockchain doesn't save any of its data in a single place. Instead, a network of computers
copies and disseminates the blockchain. Every computer in the network updates its
blockchain whenever a new block is added to the blockchain. Blockchain makes it more
challenging for someone to tamper with by dispersing that information over a network as
opposed to keeping it in a single central database. In the event that a hacker obtained a

copy of the blockchain, just one instance of the data would be at risk rather than the entire
network.
Efficient Transactions
The settlement of transactions made through a centralised authority may take many days.
For instance, if you try to deposit a check on Friday night, you could not actually see any
money in your account until Monday morning. Blockchain is active around-the-clock, seven
days a week, 365 days a year, unlike financial institutions, which only operate during regular
business hours, often five days a week. In just a few hours, transactions can be finished and
deemed secure. Transactions can be finished in as little as ten minutes. Cross-border
trades, which typically take substantially longer due to time zone concerns and the
requirement that all parties confirm payment processing, can benefit especially from this.
Private Transactions
Many blockchain networks function as open databases, making the network's transaction
history available to anybody with an Internet connection. Users can see transaction data, but
they cannot access information that would identify the users who made the transactions.
Although it is a popular misconception, blockchain networks like bitcoin are just confidential;
they are not anonymous.
A user's specific code, known as a public key, which was described earlier, is saved on the
blockchain whenever they conduct a public transaction. Not their private information. A
transaction, even when linked to a person's name, does not divulge any personal
information. However, if a person has made a Bitcoin purchase on an exchange that requires
verification, then the person's identity is still linked to their blockchain address.
Secure Transactions
A transaction's authenticity must be confirmed by the blockchain network after it is recorded.
On the blockchain, thousands of computers scramble to verify that the transaction's data are
accurate. The transaction is added to the blockchain block once it has been verified by a
machine. On the blockchain, each block has both its own distinct hash and the distinct hash
of the block that came before it. The hash code of a block changes whenever the information
on that block is altered in any manner, while the hash code of the block that comes after it
does not. It is very challenging to modify information on the blockchain without notice due to
this mismatch.

Transparency
The majority of blockchains use only open-source code. Its code can therefore be viewed by
anyone and everyone. This enables auditors to assess the security of cryptocurrencies like
Bitcoin. This also implies that there is no actual control over who edits the code for Bitcoin or
how it is controlled. As a result, anyone can recommend making improvements to the
system. Bitcoin can be upgraded if the new version of the code with the upgrade is deemed
to be sound and worthwhile by the majority of network users.
Banking the Unbanked
The fact that everyone may utilise blockchain and bitcoin, regardless of racial origin, gender,
or cultural background, is arguably their most significant feature. The World Bank estimates
that 1.7 billion adults do not have bank accounts or any other way to keep their money or
assets safe.
7
Most of these people reside in developing nations, where the economy is still in its infancy
and totally reliant on foreign exchange.
These workers frequently receive physical cash payments in the form of small salaries. They
must then conceal this actual currency in their homes or other living spaces, putting them at
risk of robbery or needless violence. The password for a bitcoin wallet can be written down,
kept on a cheap phone, or even memorised if necessary. These methods are probably
easier for the majority of individuals to conceal than a tiny amount of cash under their
mattress.
Future blockchains are also searching for ways to store medical information, property rights,
and a number of other legal contracts in addition to serving as a unit of account for wealth
storage.

Drawbacks of Blockchains
Technology Cost
Blockchain technology is not free, despite the fact that it can help consumers save money on
transaction costs. For instance, the PoW mechanism used by the bitcoin network to validate
transactions demands a tremendous amount of processing power. The annual power
consumption of Norway and Ukraine is comparable to that of the millions of machines on the
bitcoin network in the real world.
Users continue to run up their electricity bills to verify transactions on the blockchain despite
the costs associated with mining bitcoin. This is due to the fact that miners are compensated
with enough bitcoin for their time and effort when they add a block to the bitcoin blockchain.
To validate transactions on blockchains that do not use cryptocurrencies, however, miners
will need to be paid or given some other incentive.
These problems are starting to have some solutions emerging. For instance, farms for
bitcoin mining have been built using solar energy, extra natural gas from fracking operations,
or electricity from wind farms.
Speed and Data Inefficiency
The potential shortcomings of blockchain may be studied perfectly using the example of
Bitcoin. A new block can be added to the network in around 10 minutes using Bitcoin's PoW
method.
The blockchain network can only handle roughly seven transactions per second at that rate,
according to estimates (TPS). Even while Ethereum outperforms bitcoin in terms of
performance, blockchain still has limitations. For perspective, Visa's legacy brand can
process 65,000 TPS.
For years, people have been working on solutions to this problem. There are blockchains
with more than 30,000 TPS at the moment.
After rolling out an upgrade that incorporates sharding—a division of the database so that
more devices (phones, tablets, and laptops) can run Ethereum—up to 100,000 TPS is
anticipated to be possible after Ethereum's main net and beacon chain join (Sept. 15, 2022).
As a result, network membership will rise, traffic will be relieved, and transaction speeds will
rise.
The capacity of each block to hold data is the other problem. One of the most important
concerns regarding the future scalability of blockchains has been and remains the block size
controversy.

Illegal Activity
While secrecy on the blockchain network safeguards users' privacy and prevents hacks, it
also enables illicit activities and trade on the network. The Silk Road, an online dark web
illegal-drug and money laundering bazaar operating from February 2011 until October 2013,
when it was shut down by the FBI, is likely the most frequently cited example of blockchain
being used for criminal transactions.
Using the Tor Browser and the dark web, users can purchase illicit things in Bitcoin or other
cryptocurrencies and sell them without being seen. Financial service providers are required
by current U.S. rules to collect information about their clients when they open an account, to
validate each client's identity, and to ensure that they do not appear on any lists of known or
suspected terrorist organizations.This approach has both benefits and drawbacks. Anyone
can access financial accounts, but it also makes it simpler for thieves to conduct
transactions. Many have claimed that the positive uses of cryptocurrencies, such as banking
the unbanked globe, outweigh the negative uses, particularly as the majority of unlawful
conduct is still carried out using untraceable cash.
Even though it was initially used for these things, Bitcoin's openness and development as a
financial asset have actually caused illicit behaviour to move to other cryptocurrencies like
Monero and Dash.
Only a very small percentage of all Bitcoin transactions now are related to illicit behaviour
.
Regulation
Concerns concerning governmental regulation of cryptocurrencies have been raised by
many in the crypto community. Governments might conceivably make it unlawful to hold
cryptocurrencies or take part in their networks, even though it is getting more and harder to
stop something like Bitcoin as its decentralised network grows.
As major corporations like PayPal start to permit the ownership and use of cryptocurrencies
on their network, this worry has diminished over time.

What Is a Blockchain in Simple Terms?
A blockchain is essentially a decentralised database or ledger. Each node of the network has
an exact copy of the whole database, and data is stored in data structures called blocks.
Since the majority of the copies of the ledger do not reflect this modification, attempts to edit
or delete an entry in one copy of the ledger will be refused, ensuring security.
How Many Blockchains Are There?
Every day, the number of active blockchains increases at an exponential rate. By 2022, there
will be several hundred additional non-cryptocurrency blockchains in addition to the more
than 10,000 active cryptocurrencies built on blockchain.
What’s the Difference Between a Private Blockchain
and a Public Blockchain?
A public blockchain, sometimes referred to as an open or permissionless blockchain, allows
anyone to join the network and set up a node without restriction. These blockchains need to
be safeguarded using encryption and a consensus mechanism like proof of work because of
how open they are (PoW).
On the other hand, a private or permissioned blockchain needs each node to be vetted
before joining. The layers of security do not need to be as thick because nodes are
presumed to be trustworthy.
What Is a Blockchain Platform?
On top of an already-existing blockchain infrastructure, users and developers can build new
applications using a blockchain platform. Ethereum is one instance, which contains a built-in
coin called ether (ETH).
However, the Ethereum blockchain also enables the development of programmable tokens
for initial coin offers (ICOs), smart contracts, and non-fungible tokens (NFTs). All of them are
constructed around the Ethereum network's infrastructure and are protected by nodes.

Who Invented Blockchain?
Stuart Haber and W. Scott Stornetta, two mathematicians interested in implementing a
system where document timestamps could not be altered, first proposed the concept of
blockchain technology in 1991.
Cypherpunk Nick Szabo advocated utilising a blockchain to protect the bit gold digital
payment system in the late 1990s (which was never implemented).
The Bottom Line
Blockchain is finally establishing itself, in no little part because to bitcoin and
cryptocurrencies, with several real-world uses for the technology now being implemented
and researched. Blockchain, a buzzword on everyone's lips as an investor in the country,
promises to reduce middlemen while increasing accuracy, efficiency, security, and
cost-effectiveness in commercial and government activities.
It's no longer a question of if legacy organisations will adopt blockchain technology—a it's
question of when—as we get ready to enter the third decade of the technology. NFTs are
becoming more and more prevalent today, and assets are being tokenized. Blockchain will
experience significant expansion during the ensuing decades.

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