What\\\'s the difference between list and tuples?

Apart from tuples being immutable there is also a semantic distinction that should guide their usage. Tuples are heterogeneous data structures (i.e., their entries have different meanings), while lists are homogeneous sequences. Tuples have structure, lists have order.

Using this distinction makes code more explicit and understandable.

One example would be pairs of page and line number to reference locations in a book, e.g.:

my_location =(42,11)# page number, line number

You can then use this as a key in a dictionary to store notes on locations. A list on the other hand could be used to store multiple locations. Naturally one might want to add or remove locations from the list, so it makes sense that lists are mutable. On the other hand it probably doesn\'t make sense to change the page number in a location tuple while keeping the line number intact - this would give you a completely new location. On the other hand, there might be situations where it makes perfect sense to correct just the line number (without replacing the whole tuple).

There are some interesting articles on this issue, e.g. Python Tuples are Not Just Constant Lists or Understanding tuples vs. lists in Python The official Python documentation also mentions this (\\\"Tuples are immutable, and usually contain an heterogeneous sequence ...\\\").

In a statically typed language like Haskell the values in a tuple generally have different types and the length of the tuple must be fixed. In a list the values all have the same type and the length is not fixed. So the difference is very obvious.

Finally there is the namedtuple in Python, which makes sense because a tuple is already supposed to have structure. This underlines the idea that tuples are a light-weight alternative to classes and instances.