Lists can contain other lists, creating multi-dimensional structures. A 2D list (matrix) looks like: matrix = [[1, 2, 3], [4, 5, 6], [7, 8, 9]].
Access elements with multiple indices: matrix[0] returns the first row [1, 2, 3], and matrix[0][1] returns 2 (row , column ). Iterate through nested structures with nested loops: python for row in matrix: for element in row: print(element) Nested lists are useful for grids, tables, game boards, and representing mathematical matrices.
The inner lists can have different lengths. Python doesn't require rectangular structures. Giving flexibility for representing irregular data.