What is the difference between lists and sets in Python?

List — an ordered, mutable collection of elements that allows duplicates. Set — an unordered, mutable collection of unique elements that does not allow duplicates.

# Examples
my_list = [1, 2, 2, 3] # List with a duplicate
my_set = {1, 2, 3}   # Set, duplicate automatically removed

Characteristic	List	Set
Order	Ordered (by index)	Unordered
Mutability	Mutable	Mutable
Duplicates	Allowed	Not allowed (elements are unique)
Access by index	Possible	Impossible
Main purpose	Storing a sequence	Checking for uniqueness, set operations