What I can do here

Tell us what’s happening:

Your code so far


function nextInLine(arr, item) {
  // Your code here
  arr=arr+item;

  return item;  // Change this line
}

// Test Setup
var testArr = [1,2,3,4,5];

// Display Code
console.log("Before: " + JSON.stringify(testArr));
console.log(nextInLine(testArr, 6)); // Modify this line to test
console.log("After: " + JSON.stringify(testArr));

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/66.0.3359.181 Safari/537.36.

Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/stand-in-line

+ is for addition or joining strings. You can’t add things to an array with it.

JavaScript has methods designed specifically to do what the task asks for: look at thr documentation for shift, unshift, push and pop - two of those will be useful.