React Map function

 in react map function every element is going in a loop and the element or components should be in array []

like [ ] 

we can call function under function or we say that  call function under map function

we can write map function

let a = [12,3,4,5,5];

const no = a.map(function(x){

 return x*2; 

}

);

console.log(no);

and also 

function n(x){

return x*2;

}