Download to read offline
![CREATE AN ECR20 TOKEN
19
pragma solidity >=0.7.0 <0.9.0;
contract ATHULERC20
{
event Transfer(address indexed from, address indexed to, uint tokens);
event Approval(address indexed tokenOwner, address indexed spender, uint tokens);
string public constant name = "SNIT";
string public constant symbol = "SNIT";
uint8 public constant decimals = 18;
mapping(address => uint256) balances;
mapping(address => mapping (address => uint256)) allowed;
uint256 totalSupply_;
constructor(uint256 total)
totalSupply_ = total;
balances[msg.sender] = totalSupply_;
}](https://image.slidesharecdn.com/crypto-220820034252-33a76bd7/85/CRYPTO-pptx-19-320.jpg)
CRYPTO.pptx
- 1. CRYPTOCURRENCY ATHUL P SUDHEER S2MCA ROLL NO 124
- 2. HISTORY OF CURRENCY ╸BARTER SYSTEM ╸ PRECIOUS METAL ╸ GOLD BACKED CURRENCIES ╸ FIAT CURRENCY 2
- 3. BARTER SYSTEM ● Thebarter system is a system of exchange, before the introduction of the monetary system. ● Goods and services are traded for goods and services. ● This means that the parties exchange each other’s commodity directly without any mediation of money . 3 LIMITATIONS ● Lack of Double Coincidence of Wants ● Lack of a Common Measure of Value ● Indivisibility of Certain Goods
- 4. PRECIOUS METALS ● Preciousmetals was the second mode of transaction used by humans. ● Gold and silver predominantly gold began to be used as a mode of transaction. ● People started exchanging goods and services in behalf of precious metals. 4 LIMITATIONS ● Suppose a person become rich and has lots of gold in his hands and will have to travel with this gold to make a big deal ● Storage and security issue.
- 5. GOLD BACKED CURRENCIES ●Gold is better mode of transaction but human realised it is difficult to use. ● At this stage some organisation started evolving and offers, give us the gold you own and we will give you a verified paper or a currency equal to the value of gold. ● This is the rudimentary form we call a bank today. 5 LIMITATIONS ● In 1940, During the world war many countries needed a lot of money. ● Massive demand for money and limited gold reserve.
- 6. FIAT CURRENCIES ● Adecision was made in 1970s (all major countries together) that any country could print as many currencies they need. ● Which means no currency is no longer back / pegged to any commodities. ● This agreement is called Bretton Woods agreement. ● A fiat currency is money that is not backed by a physical commodity like gold, but instead backed by the government that issued it. ● Most modern currencies, such as the U.S. dollar, euro, pound and yen, are fiat money. 6
- 7.
- 8. PROBLEMS IN CURRENT BANKINGSYSTEM 8 ╸ Controlled by a central authority at every stages. ╸ Risk of inflammation due to miss management by central authority. ╸ Inefficient to handle instabilities at the time. ╸ Security and threats. ╸ The major delay present in money transfer. ╸ Banks have the ability to print more (and unlimited) money – they can simply create new cash out of thin air. ╸ In 2009 a new currency system was proposed, Which is called crypto currency . ╸ Bitcoin is the world's first cryptocurrency ,which Satoshi Nakamoto proposed.
- 9. WHAT IS CRYPTOCURRENCY? 9 ╸A cryptocurrency is a digital payment system that does not rely on bank to verify transaction. ╸ It is a peer-to-peer system that anyone anywhere can send and receive payments. ╸ when you transfer cryptocurrency funds the transactions are recorded in a public ledger. ╸ Cryptocurrency receives its name because it uses encryption to verify transactions. ╸ It is our digital cash which is fast,safe,secure and most importantly it is decentralized. ╸ Everyone uses cryptocurrency more as a digital asset than as a currency.
- 10. WHAT IS BITCOIN? HOW DOES IT WORK? 10 ╸ Bitcoin is a digital currency (cryptocurrency) which is independent of any country or geographical entity & can be used by anyone who is connected to the internet. ╸ Bitcoin purely peer to peer version of electric cash would allow online payment it to be send directly from one party to another without going to a financial institution. ╸ In 2009 Satoshi Nakamoto released bitcoin on internet. ╸ A person can send money to any other person directly without anyone's control ╸ The total supply of bitcoin is 21 million. ╸ In 21 million, 18.89 million have already be mined and circulated in the market. ╸ Today the value of a single bitcoin is nearly 50 lakhs.
- 11. WORKING? 11 TWO MAJOR TECHNOLOGIESUSED IN CRYPTOCURRENCY ARE: 1.CRYPTOGRAPHY Cryptography is the study of secure communications techniques that allow only the sender and intended recipient of a message to view its contents.The term is derived from the Greek word kryptos, which means hidden. 2.BLOCKCHAIN TECHNOLOGY Blockchain is a peer-to-peer decentralized distributed ledger technology that makes the records of any digital asset transparent and unchangeable and works without involving any third-party intermediary. It is an emerging and revolutionary technology that is attracting a lot of public attention due to its capability to reduce risks and frauds in a scalable manner.
- 12.
- 13. 13 ╸ A publicledger records all bitcoin transactions and copies are held on servers around the world.Anyone with a spare computer can set up one of these servers, known as a node. ╸ Consensus on who owns which coins is reached cryptographically across these nodes rather than relying on a central source of trust like a bank. ╸ Every transaction is publicly broadcast to the network and shared from node to node. ╸ Every ten minutes or so these transactions are collected together by miners into a group called a block and added permanently to the blockchain. This is the definitive account book of bitcoin. ╸ In much the same way you would keep traditional coins in a physical wallet, virtual currencies are held in digital wallets and can be accessed from client software or a range of online and hardware tools.
- 14. WHAT IS MINING? 14 ╸Mining is the process that Bitcoin and several other cryptocurrencies use to generate new coins and verify new transactions. ╸ It involves vast, decentralized networks of computers around the world that verify and secure blockchains – the virtual ledgers that document cryptocurrency transactions. ╸ In return for contributing their processing power, computers on the network are rewarded with new coins. ╸ It’s a virtuous circle: the miners maintain and secure the blockchain, the blockchain awards the coins, the coins provide an incentive for the miners to maintain the blockchain.
- 15. HOW TO STARTMINING? 15 1. Set up a computer with at least one graphics card. 1. Create a Ethereum wallet. 1. Join a mining pool. 1. Select the algorithm which is good for your computer. 1. Paste your wallet address to mining software and start mining.
- 16. DIFFERENT TYPES OF CRYPTOCURRENCY 16 1.MAJOR COIN ╸ BITCOIN ╸ TRON ╸ BNB 1. ALTCOIN ╸ LITECOIN ╸ RIPPLE 1. STABLE COINS ╸ USDT ╸ PAXGOLD 4 . TOKENS. ╸ BASIC ATTENTION TOKEN (BAT) ╸ WRX ╸ PANCAKE SWAP ╸ THE SANDBOX
- 17. HOW TO CREATEA TOKEN ON ETHEREUM BLOCKCHAIN 17 1.GET ETHER Getting ether on your hands has several ways. The first choice is to purchase it through fiat currencies. The other choice is to swap other tokens for Ethereum on a decentralized exchange. 2.CREATE A METAMASK ACCOUNT It is necessary to have a metamask wallet, to acquire ether. This is the second thing we must do before we create Ethereum tokens. 3.CREATE A SMART CONTRACT Solidity is a contract-oriented, high-level programming language for implementing smart contracts. Create our contract with solidity according to ERC20 standard.
- 18. 18 4.CHECK THE WORKING Ensuringthe working of contracts is the most prominent step to deploy tokens on the network. It can be done by using "brownie console" command. Once it compiles successfully, all other things get perfect. 5. DEPLOYING THE TOKEN TO THE BLOCKCHAIN Deploy our contract to the Ethereum network — well, not actually the Ethereum network, but an Ethereum test network. We can’t deploy our contract on the real Ethereum network because it would cost real money. Since we’re only practicing, we’ll use this test network and transfer a free ETH to deploy our contract.
- 19. CREATE AN ECR20TOKEN 19 pragma solidity >=0.7.0 <0.9.0; contract ATHULERC20 { event Transfer(address indexed from, address indexed to, uint tokens); event Approval(address indexed tokenOwner, address indexed spender, uint tokens); string public constant name = "SNIT"; string public constant symbol = "SNIT"; uint8 public constant decimals = 18; mapping(address => uint256) balances; mapping(address => mapping (address => uint256)) allowed; uint256 totalSupply_; constructor(uint256 total) totalSupply_ = total; balances[msg.sender] = totalSupply_; }
- 20.