Cryptocurrency is a digital currency by which we can buy or sell the things. Cryptocurrency has no physical interpretation. Cryptocurrency means

• Crypto means Secret
• Currency means medium of purchasing goods and services

When something become common it becomes interesting same thing is done with cryptocurrency. Cryptocurrency based on the technology called blockchain technology and this technology is completely decentralized. In this technology there is a large number of computer helps to complete and verify the transaction. As cryptocurrency is decentralization currency in which no third parties involve for example any bank or government. So the transaction cannot be altered or changed in blockchain. So it is good if someone hack your cryptocurrency transaction,he cannot alter it. It is totally independent currency so if we want to store cryptocurrency we need digital wallet. There is a private key is present for digital wallet. For example if I have 1 Bitcoin and I have a private key of the digital wallet then I am the owner of that 1 Bitcoin. I can access anywhere anytime to that Bitcoin by having private key. Cryptocurrency is a such kind of currency that completely revolutionized the financial environment and structure.
As cryptocurrencies are the modern currencies so it is the need of hour to keep pace with the modern world by adopting such kind of modern currencies

Peer to peer network

The history of the transactions stored in computer is called Public ledger, and that is controlled by large number of computers. if transaction is try to alter in one computer then all computer will show the change in transaction and theft will be captured this process is called peer to peer network. This transaction is completely based on blockchain and blockchain is a combination of two words block and chain which means these are the complete chain of blocks. When the transaction is started until the first block is completed then the the next block is started. There is a complete coordination of each block with one another.
The people who are maintaining and taking the responsibility of public ledger called miners and the process is called mining this all process is completely automatic and controlled by the software and computers.

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History of Cryptocurrency

As Bitcoin was first invented in 2008 but the history of cryptocurrency is considered too much old for them at start when the computer was invented we can say that the digital work was started from that time. Suppose that if we do not have the computer we cannot use cryptocurrency as a digital currency.

• In 1983 Trauma gives the idea of untraceable digital currency.
• Tom's Ideology inspire the creation of Bitcoin but its Idea was too much time ago to gain the reputation and adaptation.
• In 1989 DIGI cash started
• In 1990 Online system started
• After that in 2008 Bitcoin was invented by Satoshi Nakamoto.

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Price of Cryptocurrency [Bitcoin]

When the number of something is become fixed then their prices depend upon the its demand. This is the same process occur with cryptocurrency. If you take an example of Bitcoin the number of mining is fixed that is 21 million. No it's price in the market is depend upon its demand when there is more demand of the cryptocurrency such as Bitcoin their price will be increased. For example when musk says tesla will accept the bitcoin as currency. The price of the Bitcoin then was increased at high rate

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But in the recent past when he said that Tesla will not accept Bitcoin as a currency then the price of the Bitcoin was decreased very rapidly.

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The price graph of Bitcoin at different interval is given in the picture.

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Advantages of Cryptocurrency

• It works on complete decentralization system.
• there is no involvement of any government or any bank. So any policy made by the government or Bank or inflation rate will not effect the the cryptocurrency.
• It works on blockchain technology so it is highly secure system.
• There is no commission or transaction fee that has to be given to third party as occurred in centralized system.
• Fast and easy transaction.

Disadvantages of Cryptocurrency

• If any problem happens there is no middle person is present that can solve your problem.
• it is not eco friendly because of wastage of many resources such as electricity.
• Sometime unethical transaction are also done with cryptocurrency.

Some cryptocurrencies coins

• Bitcoin
• Ethereum
• Dogecoin
• Ripple
  
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Q 2 What is Cryptography and how does it make cryptocurrencies secure

• Cryptography is the practice and study of technology for securing communication and data in the presence of any adversities.
• It is a process by which plain text is converted into ciphertext.

Supposed that we are sending a message or data on internet to someone, so as every person has an access on internet so anyone can read other data so first of all we have to convert the data into such a form that even some person read it but cannot understand it. So plain text is a type of text that can be read and understand by anyone but the ciphertext may read by anyone but it cannot be understand by everyone because in order to read the ciphertext there is need a decryption key.
Suppose we have a message first we convert that message into numeric form then this numeric form is applied with a key called encryption key. This encryption key is used with encryption algorithms. The result of encryption algorithms and numeric key is called Ciphertext. Now the ciphertext is send to over the network to the other side of the world where the other person whose message is integrated for, It will actually use the decryption key and the ciphertext is converted into plain text and can be readable and understandable by the receiving person.

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Symmetric cryptographic key
It is a type of key in which the encryption key means sending person key and the decryption key means receiving person key is same
Asymmetric cryptographic key
It is a type of key in which encryption and decryption both keys are different.

How cryptography secure cryptocurrencies

• If there is no such technologies like Cryptography plain text will remain in a plane form that will be read by anyone and our assest will be stolen.
• There is always a public and private key in Cryptography these keys will secure our transaction that are message or any other form of information. When sender will send message it will convert to ciphertext by public key and receiver will convert to plain text by private key no other person will cause adversities in this way our currency is secure.
• With the help of cryptography you can send the private message in a secure way.

Question 3 Explore the Steem Genesis Block and Sign in as proof of completion

Step 1

In the first step we have to open the website give below
https://steemworld.org/

Step 2

In second step a box block explore os given. Then I open this box.

Step 3

As we have to open the Genesis Block so the first block is Genesis Block. Then I open the block and click Ok

Step 4

In this there are all information is given about block id, time-stamp, witness and everything in the boxes.

• Time-stamp 2016-03-24, 21:05:00
• Block id
  0000000109833ce528d5bbfb3f6225b39ee10086
• Witness initminer

Step 5

In step 5 there is sign in option is present on the upper right side. Click to sign in

Step 6

The user name and private posting key is putt and then ok

Step 7

Here is the completion of Sign in process.

All the secreenshot in question 3 part c are taken from https://steemworld.org/

Conclusion

In this lecture we have learnt a great lesson about Cryptocurrency how it was built and what was its main function. We also learnt that cryptocurrencies are the digital currency and the upcoming era is the era of these currencies such as Bitcoin.There is also a great understanding about cryptography which is a wonder for cryptocurrencies to make it Secure and to send private message data and transaction. In the last section we learn about Genesis block, that is the first block in the blockchain and also learn how to sign-in the genesis block. Thanks a lot to professor @awesononso for this excellent lecture.

Cc

@awesononso