Documentation Strings

What are Documentation Strings?

In Python, Documentation strings, or docstrings, are a type of comment used to explain the purpose of a function or a class. Docstrings are a crucial tool for programmers because they provide a convenient way of associating documentation with Python modules, functions, classes, and methods.

Syntax of Docstrings

A docstring is a string written as the first statement in the body of a function, module, class, or method definition. They are defined by using triple quotes, either single '''docstring''' or double """docstring""".

Here is an example:

1def add_numbers(x, y):
2    """This function adds two numbers together."""
3    return x + y

Accessing Docstrings

Python has a built-in help() function that can help you access this documentation whenever required.

1def add_numbers(x, y):
2    """This function adds two numbers together."""
3    return x + y

In this example, if you run this program, it will output the docstring:

Help on function add_numbers in module __main__:

add_numbers(x, y)
    This function adds two numbers together.

The Importance of Docstrings

Docstrings form the basis of automated documentation in Python, available via the help() function in the Python interpreter. This significantly increases the readability and understanding of the code - especially in larger codebases.

Moreover, many IDEs also use these docstrings to provide context-aware help and hints, enhancing the development experience.


While writing docstrings for functions, it is useful to include information about what the function does, its arguments, its return value, and any exceptions it raises. The clarity provided by comprehensive docstrings can make the process of debugging or adding features much simpler.


Docstrings are an essential part of Python programming, allowing you to embed useful information and documentation directly into your Python scripts. Well-documented code is critical to maintainable and reusable code - so it’s always good practice to be diligent in your docstring use.