Notesale: Turn your study into money

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BLOCKCHAIN DEVELOPMENT NOTES
What is Web3?
"If you want to learn more about web 3
...
Web 3
...

This is important because most of the content on these platforms is actually
developed by normal people, and currently, users do not have power to own
their content or know where exactly their data is going to be used
...


Why Blockchain? | Prerequisites
Everyone is talking about blockchain it doesn't matter which industry you
work for all of them are trying to implement blockchain
...
Everything you do
online will be saved in one ledger again we 'll talk about that later in detail
so everything we will store in one
...
If you have a transparency you can actually trust
the system the next thing is the moment we talk about later no one can
change it so the later which we create
...
The next video we are going to
implement will be on the prerequisites so if you don't know anything that's
fine you can start from today or you can wait for the next video where we
will implement
...
While some companies are still

conducting proof of concept (POC), others have already started
implementing it
...
This ledger will be transparent, allowing anyone to see it, creating
a system of trust
...
As the blockchain industry is
currently booming, and there are more vacancies for blockchain-related jobs
than any other field
...
To get involved, people can share photos and videos on
ireport
...
com,
share
their
pictures
with
blockchainpictures
...
com
...
However, there are
other implementations of blockchain that will be explored later on
...
Every time a transaction occurs, it is recorded not
only between the parties transacting but with everyone in the network
...
In Bitcoin, the data is
organized in blocks, and a hash of each block is found using algorithms such
as sha3
...
In real Bitcoin, miners get around 6
...
The timing of the blocks
in the Bitcoin network is not fixed, but on average, it is completed every ten
minutes
...
3 kilometers
...
The moment someone changes
it that block got changed it will affect the hash and that's how you know that

something has been changed and now we know who has done that let 's kick
that person out of the network
...
All the people in the network are called nodes
now the question is how you can be a node
...
This system has four main concerns: confidentiality, integrity, nonrepudiation, and authentication
...
The data received by the receiver is different from what
the sender is sending, and this ensures the integrity of the data, preventing
it from being modified
...
The only way to encrypt and
decrypt something is with the help of a key that both parties possess
...
It means that only the sender and
receiver can encrypt and decrypt messages, as no one else has access to the
key
...

The blockchain has come a long way since its inception and is now utilized
in various industries
...
With the advancements in technology,
the system continues to evolve and improve

Types of Cryptography | Blockchain
The speaker discusses two types of cryptography, symmetric key
cryptography and asymmetric key cryptography
...
On the other hand, asymmetric key
cryptography involves using two different keys, a public key for encryption
and a private key for decryption
...
B can then use the same key to decrypt the message
...
For instance, A and C would require a different
key, k3, to communicate
...
B would also possess his own private and public key
...
Overall, using public key cryptography ensures
that anyone on the network can see the encrypted message, but only the
recipient with the correct private key can decrypt it
...

As explained in a previous video, these are the four problems that need to
be addressed on a network
...
However, to achieve authentication, we need to add a
digital signature
...
In the
real world, we sign our letters to ensure authenticity, but in the virtual
world, we use digital signatures
...
This ensures that even if a third party intercepts the
message, they cannot decrypt it without the receiver's private key
...


Nodes in Blockchain
A full node is a computer which stores the entire blockchain and verifies the
nodes
...
As of October 28, 2018, the size of the blockchain was 188
GB and it is constantly increasing in size
...
In order to be a miner, a full node computer requires
a significant amount of CPU and GPU power
...

However, a full node as a standalone entity does not earn any incentives
...

Full nodes are different from partial or light nodes
...
The exact workings of
miners and their role in gate-blocking will be explained as well
...


Hashing in Blockchain
Hashing function is a mathematical function that takes arbitrary length of
numerical data and converts it into a fixed length numerical data
...
Hashing is not
encryption since it is impossible to get the original data back once the hash
value is obtained
...
It is almost impossible to retrieve the original data from
the hash value as it causes data loss
...
If even one or two bits in the
content have been tampered with, it will change the entire hash value
...
Different hashing
algorithms are used, and we can easily access them from Google search
...
Instead, we must
rely on downloading the official file from the website to ensure security
...

Moreover, we can use hash values in torrent sites, which provide features like
multiple peers
...


Merkle Tree | Merkle Root | Blockchain
Devon VD continues the series on blockchain in this video, where they
explain the use of local tree in blockchain
...

To implement this, Devon explains the use of local tree, where an even
number of nodes are required to have an odd number of transactions
...

The author also explains that the result of the local tree is the hash of the
Merkel route, which can be used to find the hash of the entire block
...


Blockchain Technology Architecture
We have to stop Leipzig
...
The previous blocking of Doctor Bark in the Youtube
stream 11 UK top blogs has led to the bloggers wanting more control over
their content
...
The import ban on a
certain stone has been recently introduced, and Blog B provides more
information on its navigation system and market value
...
The blogger in Passage B notes that star chains days are currently the
rulers of the blogging platform, but ultimately trusts their own instincts to
make their blog successful
...


Types of Blockchain
Blockchain came into existence for the bitcoin and is open plus anyone can
be a part of this network
...
Yes they are anonymous
...

It is open
...
public is best because anyone can be a part of
it now Since we are using proof of work which takes ten minutes for each
block so it is slow
...
Verde questions the necessity of a PoW when a
blockchain network is in place
...
To illustrate this
concept, Verde provides an example: If I give you a number, let's say 525, you
have to find the factors of that number
...
Now, this is easy and can be done in seconds
...
But if you don't have that,
you may lose, and that's the mathematical equation they use
...


What is Ethereum? | Blockchain
Bitcoin is a peer-to-peer electronic cash system that allows transactions
online
...

Ethereum has a special programming language called Solidity that
developers can use to create DApps
...
If you are already
familiar with Python or JavaScript, learning Solidity will be easier
...


Smart Contract | Ethereum | Blockchain
According to Ivan Verdi, smart contracts are a form of programming that
represents any type of contract, which Verdi explains are similar to if/then
contracts
...

Verdi highlights the benefits of smart contracts, including speed, security
through the use of blockchain technology, and the ability to build trust
between customers and companies
...
The
implementation of smart contracts can also help automate processes in the
car industry, which often involves middlemen like dealers and finance
companies, thus making the process faster and more secure
...
The initiative, built on the Hyper Ledger
project, is gaining popularity and drawing in big companies such as Intel and
IBM
...
One popular option is the
Fabric framework, which includes tools for creating a permissioned
blockchain channel that can be publicly viewed
...
Additionally, Hyper Nature is likened to a greenhouse for
open source products and blockchain technology
...
Ivan
explains how to set up a bank account with a balance so that you can add
and withdraw money, a simple task
...
If you come from a JavaScript
or object-oriented programming language background, such as C#, Java,
PHP, or Python, that's your choice
...
Initially, we want to
get the balance, so we'll use the name 'getBalance', following the
camelCasing style
...
However, the 'getBalance' method does not
change any value
...
This process converts
your code into bytecode, represented in opcodes
...
Compiling is
simple - you can use auto-compile or start the process manually
...
If you
encounter any issues, it may take some time to resolve
...
This includes
calculations like adding 400 or depositing funds
...
You are the boss, and everything
is working within your environment
...
Now we want to run it on a test network or maybe
on the main network
...

Once you select injected web three, you can see the default option which is
Ring B
...
When deploying, you have to pay the Ether's fee
...
Once you confirm the notification that

pops up, the contract is deployed
...
The same thing will work on the main network, so
just switch back to the main network, buy some Ether's, and you will be good
to go
...


Smart Contract with Front End | Blockchain
Evans Verde is explaining how to connect a smart contract to another smart
contract in a new video
...
In this example, we will explore how to prove that
...
On the web
page, you want to access a web page not on the above screen
...
When expanded, this
code leads to connecting your webpage with the smart contract
...
First,
we need ABI
...
If
you've already watched the previous video, you'll have the smart contract set
up
...
The type of UI we need is a text
field where you can enter the amount, and then you will be getting a UI
...
The moment you say
"enter" it will take some time, and you can see that your server has started
...
You can easily install it on your
machine through NPM or use it as your JavaScript library
...
eth
...
html
followed by the balance value you want to display
...
It's important to note that displaying the
balance is the only desired outcome, so there's no need to take further
action
...


Smart Contract with Web Front End Part 2
Blockchain
We need to perform a deposit by clicking on the button with the ID "deposit
...
Before fetching the value entered in the text field for the deposit
amount, we declare and initialize a variable for the amount to 0
...

Additionally, we need to handle the transaction going from pending to
mined, which may take some time, by using the then() function with an
anonymous function to get all of the accounts
...
After the deposit is
successful, we need to wait for the transaction to be mined and we can verify
the balance by checking the transaction and the balance in the console
...

NFTs are unique tokens stored on blockchain technology, which ensures that
each token has a distinct value
...
NFTs also offer the potential for artists to earn more
from their work, as well as for individuals to sell their own courses online as
NFTs
...

NFT, which stands for non-fungible token, has been gaining popularity
recently
...
People are now
creating collections of NFTs, which can also be auctioned off
...
This has led

to people selling their own non-fungible tokens, including Jack Dorsey, the
CEO of Twitter, who is selling his first tweet as an NFT
...




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