Array Lower & Upper Bounds
The topic focusing on Lower and Upper Bounds, as well as Array Slicing in Python.
The lower bound in an array is the left most index in an array.
In Python lists(the Python version of arrays) all arrays start at index 0 and therefore the lower bound is always zero.
In Python lists the upper bound is always the index of the last item in the list, with works out to be the length of the list minus 1 (because Python starts Indexing at zero).