Python Basics: Exploring the Six Common Data Types with Code Examples

Common Python Data Types

Python 3 defines six built‑in types: Number, String, List, Tuple, Dictionary and Set.

Number

int – integer values.

num = 32
print(num)

32

float – floating‑point numbers.

# float type
num1 = 3.21
print(num1)

3.21

bool – subclass of int with values True and False.

bool1 = True
bool2 = False
print(bool1)
print(bool2)
print(4 < 3)   # False
print(11 > 8)  # True

True
False
False
True

String

Strings are sequences of characters (letters, digits, underscores, Chinese characters, etc.) delimited by single or double quotes. Triple quotes allow multi‑line literals.

str1 = "hello"
str2 = 'world'
str3 = '''
床前明月光,
疑是地上霜,
举头望明月,
低头思故乡.
'''
print(str1, str2, str3)

hello world
床前明月光,
疑是地上霜,
举头望明月,
低头思故乡.

List

Lists are mutable sequences defined with []. Elements may be of heterogeneous types and may be nested.

list1 = ['张三', '李四', '王五', '陈六', '徐七']
print(list1)

list2 = [12, 34, 56, 5.32, True, False, "hello"]
print(list2)

['张三', '李四', '王五', '陈六', '徐七']
[12, 34, 56, 5.32, True, False, 'hello']

Tuple

Tuples are immutable sequences defined with ().

tup = (12, 43, 9, 87, True, False, "world")
print(tup)

(12, 43, 9, 87, True, False, 'world')

Dictionary

Dictionaries map immutable keys to values and are defined with {}.

user = {"name": "李四", "age": 35, "sex": "男", "weight": 183}
print(user)

{'name': '李四', 'age': 35, 'sex': '男', 'weight': 183}

Set

Sets store unordered unique elements and are also defined with {}.

set1 = {121, 67.36, True, False}
print(set1)

{False, True, 67.36, 121}