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Data Types

Python has several built-in data types: int, float, str, bool, list, tuple, set, dict, and None.

Python Data Types

Every value in Python has a data type. Python's built-in types cover most programming needs.

Numeric Types

int: Integers (1, -5, 1000000)
float: Decimals (3.14, -0.5)
complex: Complex numbers (2+3j)

Text Type

str: Strings ("hello", "world")

Boolean Type

bool: True or False

Type Conversion

Convert between types using int(), float(), str(), bool().

Syntax

<pre><code># Integers
age = 25
big_num = 1_000_000  # underscores for readability

# Floats
price = 9.99
pi = 3.14159

# Strings
name = "Alice"
greeting = "Hello, " + name  # concatenation
multiline = """This is
a multiline
string"""

# Booleans
is_active = True
is_logged_in = False

# None (absence of value)
result = None

# Type conversion
num_str = "42"
num_int = int(num_str)    # 42
num_float = float(num_str)  # 42.0
back_str = str(num_int)   # "42"

# Check type
print(isinstance(age, int))  # True
</code></pre>

Revision Notes

• int, float, complex — numbers
• str — text (immutable)
• bool — True/False
• None — absence of value
• int(), float(), str() for conversion
• isinstance() checks type membership

Variables Operators