Integer
In one line
An integer is a whole number — positive, negative, or zero — with no fractional or decimal part.
In simple words
An integer is a number without a decimal point. Examples include 5, -3, 0, 42, and -1000. Integers are used for counting, indexing, and any situation where fractional values do not make sense.
Most languages distinguish integers from floating-point numbers (floats), which have decimal parts. For example, 7 is an integer, but 7.5 is a float. In JavaScript, all numbers are technically floats, but in languages like Python, Java, and C, integers and floats are distinct types.
Integers are efficient for the computer to store and calculate with. They are the default choice for loop counters, array indices, and anything you count or enumerate.
Example
age = 25 # integer
temperature = -5 # negative integer
print(type(age)) # <class 'int'>
print(7 / 2) # 3.5 (float, not integer)
print(7 // 2) # 3 (integer division)In Python, int is a distinct type. Integer division // discards the fractional part.
Common confusions
Confused with: float
The difference: An integer is a whole number with no decimal part (7); a float has a fractional part (7.5). Operations like 7/2 may produce a float even from integer inputs.
Related terms
Related Resources
Related Lessons
- Data Types
Integers are covered as a core data type
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