what does i in range = to code example

Example 1: range python 3

# range(start, stop, step)
  # start = index to begin at (INCLUSIVE)
  # stop = generate numbers up to, but not including this number (EXCLUSIVE)
  # step = (can be omitted) difference between each number in the sequence

arr = [19,5,3,22,13]

# range(stop)
for i in range(len(arr)):
    print(arr[i]) # prints: 19, 5, 3, 22, 13

# range(start, stop)
for i in range(2, len(arr)):
    print(arr[i]) # prints: 3, 22, 13
    
# range(start, stop, step)
for i in range(0, len(arr), 2):
    print(arr[i]) # prints: 19, 3, 13
    
# reverse:
for i in range(len(arr)-1, -1, -1):
    print(arr[i])

Example 2: python range of array

>>> new_list = [1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> print(new_list[5:9])
[6, 7, 8, 9]