title: What is the variable "i" in loops?
body: <p>I saw the following code in a coding challenge, I don't know why it returns 3, but check the code and tell me what do u think.</p>
  <pre><code>myList = [1,2,3,4]
  for i in myList:
     i += 1
  print(myList[-2])
  </code></pre>
  <p>When I saw the code I said it will print 4 because in the loop we added 1 in all integers in the list, and <code>[-2]</code> is supposed to give me the second-last value, which is 4 according to what I think.</p>
  <p>I know I'm missing something here but I don't know what it is, so if anyone could explain this to me I'll appreciate it. Probably I'm not understanding <code>i</code>, I'm not sure.</p>