What is the purpose of the buildList function?

Hi there! In the video you've linked here between the times of 3:00 and 3:16 the buildList function is called not once, but twice on both lines 42 and 44. The function is defined to accept an array. The two arrays we send in (one at a time) are our arrays containing our questions that we got correct and our questions that we got incorrect. Inside the function we use concatenation with the += operator to "build up" an html string. The function is started by appending the opening tag for the ordered list. Then we loop through each item inside the array we sent in. For each item in that array we're going to append a list item containing the question we got correct or incorrect. When that part is complete we'll append a closing ordered list tag and return the resulting string to the place that it was called. And if you look on lines 42 and 44, you'll see that the returned string is appended using the += operator to the html variable. Finally, we print out the entirety of the html variable to the page.

Hope this helps, but let me know if something is unclear!