Added ERC20 token basic smart contract

Ethereum/ERC-20/ERC20Token.sol

@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-3.0
+
+pragma solidity ^0.8.7;
+
+//ERC 20 token smart contract where we made new ERC20 token, we can send it to other accounts as well as we can give permission to particular person to spend token on our behalf.
+contract myToken { 
+
+   //name of the token
+   string public name = "keth";
+   //symbol for token
+   string public symbol= "kth";
+
+   //deployer will be owner 
+   address owner = msg.sender;
+   uint8 public decimal= 18;  //used with matic
+
+
+   uint256 public totalToken = 1000000 * (10 ** decimal);
+
+   //this will return balance 0 initially but will show total token after constructor()
+   mapping (address => uint256) public balanceof;
+
+   //contructor will assign all the token supply to owner
+   constructor() {
+       balanceof[owner] = totalToken;
+       emit Transfer(msg.sender, owner, totalToken);
+   }
+
+   //Event for transfer 
+   event Transfer(address indexed _from, address indexed _to, uint256 value);
+   function transfer(address _to, uint256 _val) public returns(bool success)
+   {
+      require(balanceof[owner] >= _val, "Insufficient balance ");
+      balanceof[_to] += _val;
+      balanceof[owner] -= _val;
+      uint balNow = totalToken - _val;
+
+      emit Transfer(owner , _to, _val);
+
+      if(balNow == balanceof[owner]){
+          return true;
+      }
+      else{
+          return false;
+      }
+
+
+   }
+   //this mapping will keep track of who is allowed to spend token of owner and how much.
+   mapping (address => mapping( address => uint256)) public spendingData;
+
+   //event will fire once approval function is called
+   event Approval(address indexed _owner, address indexed spender, uint256 limit);
+   function approval (address _spender, uint256 _val) public returns(bool success){
+       spendingData[owner][_spender]= _val;
+       balanceof[_spender]+=_val;
+       emit Approval(owner,_spender,_val);
+       return true;
+   }
+
+   function transferFrom (address _spender, address _to, uint val)public returns(bool success) {
+       require(spendingData[owner][_spender]>= val, "Permission denied");
+       require(balanceof[_spender]>= val , "Insufficient balance");
+       balanceof[_to] += val;
+       balanceof[_spender]-=val;
+       emit Transfer(_spender, _to, val);
+       spendingData[owner][_spender] -= val;
+       return true;
+   }
+
+
+
+
+
+}