Variables in Python

Learn about variable types in Python including integers, floats, strings, and booleans

Introduction to Variables

Variables in Python are containers for storing data values. Unlike some other programming languages, Python doesn’t require explicit declaration of variable types - the type is automatically determined based on the value assigned.

Variable Types

Python supports several fundamental data types:

Integer (INT)

Stores whole numbers without decimal points.

variable_de_tipo_entero = 10
print(f"Variable de tipo entero: {variable_de_tipo_entero}")
print(type(variable_de_tipo_entero))  # <class 'int'>

Integers can be positive, negative, or zero. Examples: 100, 260, -50, 0

Float (FLOAT)

Stores numbers with decimal points (real numbers).

variable_de_tipo_real = 54.8
print(f"Variable de tipo real: {variable_de_tipo_real}")
print(type(variable_de_tipo_real))  # <class 'float'>

Floats can represent both whole numbers and decimals. Examples: 1.24, 2.0, 5.7, 3.14159

String (STRING)

Stores text and character sequences.

variable_de_tipo_caracteres = "Un saludo muy especial a todos los coders"
print(f"Variable de tipo caracteres: {variable_de_tipo_caracteres}")
print(type(variable_de_tipo_caracteres))  # <class 'str'>

Strings can be enclosed in single quotes ('text') or double quotes ("text"). Both are valid in Python.

Boolean (BOOL)

Stores logical values - either True or False.

variable_de_tipo_booleano = True
print(f"Variable de tipo booleano: {variable_de_tipo_booleano}")
print(type(variable_de_tipo_booleano))  # <class 'bool'>

Booleans are commonly used in conditional statements and logical operations. Only two values are possible: True or False.

Complete Example

Here’s a complete example demonstrating all variable types:

# Declare variables of different types
variable_de_tipo_entero = 10
variable_de_tipo_real = 54.8
variable_de_tipo_caracteres = "Un saludo muy especial a todos los coders"
variable_de_tipo_booleano = True

# Display variables and their types
print(f"Variable de tipo entero: {variable_de_tipo_entero}")
print(f"Variable de tipo real: {variable_de_tipo_real}")
print(f"Variable de tipo caracteres: {variable_de_tipo_caracteres}")
print(f"Variable de tipo booleano: {variable_de_tipo_booleano}")

Variable Naming Conventions

Python variable names should:

• Start with a letter or underscore
• Contain only letters, numbers, and underscores
• Be descriptive and use snake_case for multi-word names
• Avoid Python reserved keywords

Type Checking

You can check the type of any variable using the type() function:

variable1 = 100
variable2 = 3.14
variable3 = "Hello"
variable4 = False

print(type(variable1))  # <class 'int'>
print(type(variable2))  # <class 'float'>
print(type(variable3))  # <class 'str'>
print(type(variable4))  # <class 'bool'>

Key Takeaways

• INT: Whole numbers only (e.g., 100, 260)
• FLOAT: Numbers with decimals (e.g., 1.24, 5.7)
• STRING: Text values (e.g., 'Juan', 'Compras')
• BOOL: Logical values (True or False)