difference between set and list in python

1'''
2In python, a list is a collection of values in a specific order.
3There can be several times the same value
4[4,8,9,5,4,1,3,4] is a valid list in python
5
6In a set, all values has to be unique.
7It is better to use sets compared to lists as much as possible,
8because of its speed to retrieve data and space memory economy.
9Diferent methods are available for sets and lists.
10I will let you discover them on this well-done website : 
11https://www.datacamp.com/community/tutorials/sets-in-python
12'''