Summary: in this tutorial, you’ll learn about the Python boolean data type, falsy and truthy values.
Introduction to Python Boolean data type #
In programming, you often want to check if a condition is true or not and perform some actions based on the result.
To represent true and false, Python provides you with the boolean data type. The boolean value has a technical name as bool
.
The boolean data type has two values: True
and False
.
Note that the boolean values True
and False
start with the capital letters (T
) and (F
).
The following example defines two boolean variables:
is_active = True
is_admin = False
Code language: Python (python)
When you compare two numbers, Python returns the result as a boolean value. For example:
x = 20
y = 10
result = x > y
print(result)
result = x < y
print(result)
Code language: Python (python)
Output:
True
False
Code language: PHP (php)
Also, comparing two strings results in a boolean value:
x = 'a'
y = 'b'
result = x > y
print(result)
result = x < y
print(result)
Code language: Python (python)
Output:
False
True
Code language: PHP (php)
The bool() function #
To find out if a value is True
or False
, you use the bool()
function. For example:
result = bool('Hi')
print(result)
result = bool(100)
print(result)
result = bool(0)
print(result)
Code language: Python (python)
Output:
True
True
False
Code language: PHP (php)
The output indicates some values evaluate to True
and the others evaluate to False
.
Falsy and Truthy values #
When a value evaluates to True
, it’s truthy. If a value evaluates to False
, it’s falsy.
The following are falsy values in Python:
- The number zero (
0
) - An empty string
''
False
None
- An empty list
[]
- An empty tuple
()
- An empty dictionary
{}
The truthy values are the other values that aren’t falsy.
Note that you’ll learn more about the None
, list
, tuple
, and dictionary
in the upcoming tutorials.
Summary #
- Python boolean data type has two values:
True
andFalse
. - Use the
bool()
function to test if a value isTrue
orFalse
. - Falsy values evaluate to
False
whereas truthy values evaluate toTrue
. - Flasy values are the number zero, an empty string,
False
,None
, an empty list[]
, an empty tuple()
, and an empty dictionary{}
. - Truthy values are the values that are not Falsy.