Give Sibling Elements a Unique Key Attribute lll

Tell us what’s happening:
hello .
i have passed this challenge, but i am really confuse with it ?
what is the parameter mean? in the map ,
and the key … what is it , i have never see it…

Your code so far

const frontEndFrameworks = [

function Frameworks() {
  const renderFrameworks,b)=>{
    return <li key={b}>{a}</li>
  return (
      <h1>Popular Front End JavaScript Frameworks</h1>

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.99 Safari/537.36.

Link to the challenge:

First you should look up how map function works. MDN does a good explanation of it. Basically what it does is a parameter is value and b is index. So you are giving <li key> index numbers and its values inside <li> tags. This you do to dynamically generate a list.

Your code has been blurred out to avoid spoiling a full working solution for other campers who may not yet want to see a complete solution. In the future, just post a section of a solution you do not understand instead of the entire solution.

Thank you.