Also, pop returns that value that was removed, remove doesn’t.

The effects of the three different methods to remove an element from a list:

remove removes the first matching value, not a specific index:

>>> a = [0, 2, 3, 2]
>>> a.remove(2)
>>> a
[0, 3, 2]

del removes the item at a specific index:

>>> a = [9, 8, 7, 6]
>>> del a[1]
>>> a
[9, 7, 6]

and pop removes the item at a specific index and returns it.

>>> a = [4, 3, 5]
>>> a.pop(1)
3
>>> a
[4, 5]

Their error modes are different too:

>>> a = [4, 5, 6]
>>> a.remove(7)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: list.remove(x): x not in list
>>> del a[7]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IndexError: list assignment index out of range
>>> a.pop(7)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IndexError: pop index out of range

Good question! A simple difference is pop() returns the item removed so it can be assigned a different label while del simply removes the item. If you use pop() and do not assign a new label to the returned object it is essentially performing the same function as del. The list of book title strings is actually a list of references that point to string objects stored in memory. Each string object "id" is the address in memory of the stored object. ```python b1 = "book title 1" b2 = "book title 2" b3 = "book title 3" b4 = "book title 4" book_list = [b1, b2, b3, b4] print(book_list) ['book title 1', 'book title 2', 'book title 3', 'book title 4'] print([id(b1), id(b2), id(b3, id(b4)]) [139996358750368, 139996358750256, 139996358750592, 139996358750648] print([id(book) for book in book_list]) [139996358750368, 139996358750256, 139996358750592, 139996358750648] saved = book_list.pop(0) print(saved) book title 1 print(id(saved)) 139996358750368 ``` In a more detailed look, pop() returns the "id" reference removed so that it can be assigned to another label or used in a subsequent statement. The label saved is assigned to the first book popped from the book list. So, use pop() when you want to have access to the removed item for another purpose, and use del when you no longer want the item. Edit: to comment on “garbage collection”. Garbage collection happens when an object is removed from memory and the memory freed for other uses. This occurs when all references to an object are removed. pop() removed the list’s reference to object (count goes down by 1). If count is now zero, object maybe garbage collected. If a label is assigned to the popped object, this adds a new reference (count goes up by 1). So labeling a pop becomes a wash (no net change in reference count). del removes the label (the count goes down by 1) but not the object. Using del b4 simply removes the label b4 but not the object referenced by b4 since the string “book title 4” is still referenced by the list. Post back if you have more questions. Good luck!!