nestingyou can create lists of lists of listsand so on of the category "mutable sequencein terms of our type category qualifierslists are mutable ( can be changed in placeand can respond to all the sequence operations used with stringssuch as indexingslicingand concatenation in factsequence operations work the same on lists as they do on stringsthe only difference is that sequence operations such as concatenation and slicing return new lists instead of new strings when applied to lists because lists are mutablehoweverthey also support other operations that strings don'tsuch as deletion and index assignment operationswhich change the lists in place arrays of object references technicallypython lists contain zero or more references to other objects lists might remind you of arrays of pointers (addressesif you have background in some other languages fetching an item from python list is about as fast as indexing arrayin factlists really are arrays inside the standard python interpreternot linked structures as we learned in thoughpython always follows reference to an object whenever the reference is usedso your program deals only with objects whenever you assign an object to data structure component or variable namepython always stores reference to that same objectnot copy of it (unless you request copy explicitlyas preview and referencetable - summarizes common and representative list object operations it is fairly complete for python but for the full storyconsult the python standard library manualor run help(listor dir(listcall interactively for complete list of list methods--you can pass in real listor the word listwhich is the name of the list data type the set of methods here is especially prone to change-in facttwo are new as of python table - common list literals and operations operation interpretation [an empty list [ 'abc' {}four itemsindexes ['bob' ['dev''mgr']nested sublists list('spam'list of an iterable' itemslist of successive integers list(range(- ) [iindexindex of indexslicelength [ ][jl[ :jlen(ll lists and dictionaries concatenaterepeat