What does * and ** mean in Python function parameters?

General Discussions
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1

I’m trying to understand how *args and **kwargs work in function definitions like:

python
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def foo(x, y, *args):  
    pass  

def bar(x, y, **kwargs):  
    pass

What exactly does the * and ** syntax mean in Python function parameters, and when should I use them?

I’m exploring how Python ** behaves when accepting keyword arguments.

2

I use *args when I want my function to accept any number of extra positional arguments.

It’s perfect when you’re not sure how many inputs you’ll receive. For example:

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def log_events(event_type, *args):
    for item in args:
        print(f"{event_type}: {item}")

So calling log_events(“ERROR”, “disk full”, “connection lost”) prints each with the same prefix.

It gives my functions more flexibility without changing the base signature.

3

@anjuyadav.1398 For me, **kwargs is super useful when I want to allow optional named parameters.

Say I have a function that builds a user profile:

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def create_user(name, **kwargs):
    print(f"Name: {name}")
    for key, value in kwargs.items():
        print(f"{key}: {value}")

Then I can call create_user(“Sana”, age=30, location=“Berlin”).

This is where Python ** shines, you pass keyword arguments and handle them dynamically.

4

I often use both in the same function when I want full control:

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def report(*args, **kwargs):
    print("Values:", args)
    print("Options:", kwargs)

Calling report(1, 2, 3, verbose=True, output=“json”) gives me a nice split between data and config.

It’s powerful when designing utility functions or decorators where the input isn’t fixed.