Prerequisites

Metamask browser extension
Some Rinkeby test Ether (get some from here)

Jump right in

We are going to 👨‍💻

write a smart contract ✒️
Play around with it 😵
deploy it to Rinkeby testnet 🚀

What is Remix IDE

Remix is used for the entire journey of contract development as well as act as a playground for learning and teaching Ethereum.

Write a smart contract ✒️

We will learn some basic features of Remix as we go through,Now let's jump right in and create Counter.sol add new contract.gif

Copy and paste if you are lazy 😉

// SPDX-License-Identifier: Unlicensed
pragma solidity ^0.8.0;

contract Counter{
    uint public count;
    function increment() external{
        count++;
    }
    function decrement() external{
        count--;
    }
}

Lets go through the code

count is a state variable that can have value 0,1,2,...
increment() adds 1 with count at each call
decrement() subtracts 1 from count at each call

Piece of cake, right??

Remix interface

These are 3 basic options

File explorer : does the usual stuff with files🥴️
Solidity compiler : compiles .sol file selected on File explorer
Deploy and run : Deploys the contract so that we can play around with it

Deploy the contract 🚀

local deploy.gif

Why Different color buttons

To understand this, we need to know some basic stuff

Blockchain are made up of blocks,Blocks are made up of transactions
Examples of transactions are sending ETH,changing state variable values
Transactions require some payment called gas 💸
blue buttons : Does not cause state changes,it will only return a value stored in the contract ,so it won’t cost you anything in gas fees.
orange button : Create a transaction and thus cost gas.

Play around

test run.gif

Those ✅ are indicating transactions

Lets deploy it to Rinkeby Testnet 🚀

Change ENVIRONMENT to Injected Web3
Press Deploy
Confirm the Metamask request

Congratulations you have successfully deployed smart contract to testnet,It'll live there forever 🎉🎉

Finishing things off

image 1.1.png We can make transactions like before,but have to pay some gas to do so,But now all transactions are logged publicly at https://rinkeby.etherscan.io