Now we'll look at a number of data types that are built-in as well as some that are part of Python's standard library. We'll start with Python's numeric types. These include three built-in types: int, float, and complex, plus the standard library types Fraction and Decimal.

We'll also look at strings, str, and simple collections, tuple. These are more complex than numbers because they contain multiple items. Since their behavior is less complex than the kinds of objects we'll see in later chapters, they serve as a good introduction to the general concept of sequences in Python.

Note the capitalization of the names of Fraction and Decimal. The built-in type names start with a lowercase letter. Types that we must import have a module name that starts with a lowercase letter, but the type name starts with a capital letter. This convention is widespread, but not universal.

All of the types we'll look at in this chapter have the common feature of immutability. This concept...