Welcome back, young programmer! Today, we're stepping into a new Python realm: Nested Lists. A nested list is essentially a list containing other lists crucial for managing intricate data, like a grocery list, where each item is a category containing a list of items. Our goal? To make you comfortable with nested lists and show you some advanced operations they can perform. So, buckle up!

Nested lists are lists within lists, key to managing complex datasets. Here's an example of a simple nested list:

Three lists reside within a larger list. But how do we access and modify the elements of these sublists? Let's delve into this.

We can access items in nested lists with indices, similar to the flat lists we covered in the previous unit. In Python, indexing runs from 0 (from left to right) or -1 (from right to left). To access elements of sublists, we use two indices. Let's illustrate this:

Here, [0][0] fetched 1 from the first sublist, and [1][2] fetched "cherry" from the second sublist. references the third element in the last list, which is the same element as .