Built-in Data Types

Python Tutorials - Herong's Tutorial Examples

∟Built-in Data Types

This chapter provides introductions and tutorial examples about built-in data types. Topics include introductions to common features of all data types; some basic data types: NoneType, bool, int, float, bytes, str, tuple, list and dict.

Introduction to Data Type

Common Features of All Data Types

Data Type - NoneType for Nothing

Data Type - 'bool' for Boolean Values

Data Type - 'int' for Integer Values

Data Type - 'float' for Real Numbers

Data Type - 'bytes' for Byte Sequence

Data Type - 'str' for Character String

Data Type - 'tuple' for Immutable List

Data Type - 'list' for Mutable List

Data Type - 'dict' for Dictionary Table

Takeaways:

All data in a Python program is represented by objects.
Every object has an identity, a type and a value. You can use id(object) and type(object) to see its identity and data type.
The value of an immutable object can not be changed.
Every object can be implicitly casted to a Boolean value.
"NoneType" has a single object, the null object, named as "None".
"bool" has two objects named as "True" and "False".
"int" is immutable and have objects for all integer values.
"float" is immutable and can store any real number in double precision (using 8-byte storage) format according to the IEEE 754 standard.
"bytes" is immutable and can store any sequence of bytes.
"str" is immutable and can store any sequence of Unicode characters.
"tuple" is immutable and can store any sequence of object references.
"list" is mutable and can store any sequence of object references.
"dict" is mutable and can store any collection of key-value pairs.