Let us study the following smart contract

pragma solidity >=0.4.16 <0.8.0;
contract FirstContract{
    string _name;
    function setName(string name) public{
        _name = name;
    }
    function getName() constant public returns(string){
        return _name;
    }
}

The First Line pragma solidity >=0.4.22 <0.6.0; is telling the smart contract compiler which version of solidity compiler your code is using.

At line 2, FirstContract could be replaced by any names, this is the place for you to define the name of your contract.

Inside the curly brackets, there is a string variable called _name, this will occupy space and stored in the blockchain.

Also, there are two functions: setName() and getName().

setName takes a string input name. Its type of visibility is public, which means it can be called both internally and externally. Inside the function, the parameter name will be replacing the existing value stored by _name. As this function changed data in blockchain, it will cost ether.

Another function getName,