# Python math.gcd() Method

This tutorial will guide you on the function syntax, parameters, return values and provide several practical examples to illustrate its functionality.

Python's `math.gcd()` method is a powerful tool that returns the greatest common divisor of two numbers. In simple terms, it allows us to find the the largest integer that can divide both numbers without leaving a remainder.

## Import the Python Math Module

Before we can use the `math.gcd()` function, we need to import the math module:

``````import math
``````

## Basic Function Usage

The `math.gcd()` function takes two arguments and returns the greatest common divisor of the two numbers.

If either of the numbers is zero, it returns the absolute value of the non-zero number.

The following example demonstrates the basic usage of the `gcd()` function.

``````import math
print(math.gcd(60, 48))
``````

Output:

``````12
``````

## Example with Zero

What happens if one of the parameters is set to 0?

``````import math
print(math.gcd(0, 8))
``````

Output:

``````8
``````

In this case, the function returns the first non-zero number. This is because the greatest common divisor of 0 and any number is the absolute value of that number.

## Working with Negative Numbers

The `math.gcd()` function also works with negative numbers. It will always return a non-negative result.

``````import math
print(math.gcd(-60, 48))
``````

Output:

``````12
``````

Similarly, the output is `12`, because the `gcd` of negative values is similar to that of their positive equivalents.

## Conclusion

This tutorial has introduced you to Python's `math.gcd()` function, showing you how to use it to find the greatest common divisor of two numbers. It's a useful function in many different mathematical and practical contexts, and understanding how to use it effectively will be a valuable addition to your Python toolset.