A Collection of New Information

In this chapter, you learned the following:

• Sets are used in Python to store unordered collections of unique values. They support the same operations as sets in mathematics.

• Tuples are another kind of Python sequence. Tuples are ordered sequences like lists, except they are immutable.

• Dictionaries are used to store unordered collections of key/value pairs. The keys must be immutable, but the values need not be.

• Looking things up in sets and dictionaries is much faster than searching through lists. If you have a program that is doing the latter, consider changing your choice of data structures.