# lists and tuples are essentially the same
# lists are delimited by brackets, []; tuples by parentheses, ()
>>> a = [ 1, 2, 3 ]
>>> b = (4, 5, 6)
>>> a[0]
Out[4]: 1
>>> b[0]
Out[5]: 4
>>> a[1:3]
Out[6]: [2, 3]
>>> b[1:3]
Out[7]: (5, 6)

# lists are mutable, tuples are not
>>> a[0] = 'hello'
>>> a
Out[9]: ['hello', 2, 3]
>>> b[0] = 'bye'
Traceback (most recent call last):
  File "/Users/rcd/Library/Enthought/Canopy_64bit/User/lib/python2.7/site-packages/IPython/core/interactiveshell.py", line 2721, in run_code
    exec code_obj in self.user_global_ns, self.user_ns
  File "<ipython-input-10-dc8938370f46>", line 1, in <module>
    b[0] = 'bye'
TypeError: 'tuple' object does not support item assignment

# tuples are commonly returned by Python functions
>>> zip(a, b)
Out[11]: [('hello', 4), (2, 5), (3, 6)]