What method adds an item to the end of a list in Python?

The `append` method adds one item to the end of a Python list. Calling `items.append(value)` changes the existing list in place and returns `None`, rather than creating and returning a second list.

That single-item behavior is the key distinction from nearby methods. `extend(iterable)` adds each element from an iterable, while `insert(index, value)` places one item at a chosen position. Python lists are mutable sequences, so appending is an efficient and familiar way to grow a list as a program processes data.

A frequent surprise is what happens when the appended value is itself a list. `items.append([3, 4])` adds the nested list as one element; it does not add `3` and `4` separately. To add those elements individually, use `items.extend([3, 4])`. The method’s name reflects its effect on the list, not a return value, so assigning `result = items.append(5)` leaves `result` as `None`.