Python Function Parameters and Arguments Last Updated : 19 Dec, 2024 Comments Improve Suggest changes Like Article Like Report Parameters are variables defined in a function declaration. This act as placeholders for the values (arguments) that will be passed to the function. Arguments are the actual values that you pass to the function when you call it. These values replace the parameters defined in the function. Although these terms are often used interchangeably, they have distinct roles within a function. This article focuses to clarify them and help us to use Parameters and Arguments effectively.Table of ContentParametersArgumentsTypes of arguments in pythonParametersA parameter is the variable defined within the parentheses when we declare a function. Example: Python # Here a,b are the parameters def sum(a,b): print(a+b) sum(1,2) Output3 ArgumentsAn argument is a value that is passed to a function when it is called. It might be a variable, value or object passed to a function or method as input. Example: Python def sum(a,b): print(a+b) # Here the values 1,2 are arguments sum(1,2) Output3 Types of arguments in pythonPython functions can contain two types of arguments:Positional ArgumentsKeyword ArgumentsPositional ArgumentsPositional Arguments are needed to be included in proper order i.e the first argument is always listed first when the function is called, second argument needs to be called second and so on.Example: Python def fun(s1,s2): print(s1+s2) fun("Geeks","forGeeks") OutputGeeksforGeeks Note: The order of arguments must match the order of parameters in the function definition.Variable-Length Positional ArgumentsTo handle multiple arguments within the function, you can use *args. Python def fun(*args): # Concatenate all arguments result = "".join(args) print(result) # Function calls fun("Geeks", "forGeeks") # Two arguments To read in detail, refer - *args and **kwargs in PythonKeyword ArgumentsKeyword Arguments is an argument passed to a function or method which is preceded by a keyword and equal to sign (=). The order of keyword argument with respect to another keyword argument does not matter because the values are being explicitly assigned. Python def fun(s1, s2): print(s1 + s2) # Here we are explicitly assigning the values fun(s1="Geeks", s2="forGeeks") OutputGeeksforGeeks Comment More infoAdvertise with us Next Article Keyword and Positional Argument in Python koushikd1590 Follow Improve Article Tags : Python Python-Functions Practice Tags : pythonpython-functions Similar Reads Python Functions Python Functions is a block of statements that return the specific task. The idea is to put some commonly or repeatedly done tasks together and make a function so that instead of writing the same code again and again for different inputs, we can do the function calls to reuse code contained in it ov 11 min read Python def Keyword Python def keyword is used to define a function, it is placed before a function name that is provided by the user to create a user-defined function. In Python, a function is a logical unit of code containing a sequence of statements indented under a name given using the âdefâ keyword. In Python def 6 min read Difference between Method and Function in Python Here, key differences between Method and Function in Python are explained. Java is also an OOP language, but there is no concept of Function in it. But Python has both concept of Method and Function. Python Method Method is called by its name, but it is associated to an object (dependent).A method d 3 min read First Class functions in Python First-class function is a concept where functions are treated as first-class citizens. By treating functions as first-class citizens, Python allows you to write more abstract, reusable, and modular code. This means that functions in such languages are treated like any other variable. They can be pas 2 min read Assign Function to a Variable in Python In Python, functions are first-class objects, meaning they can be assigned to variables, passed as arguments and returned from other functions. Assigning a function to a variable enables function calls using the variable name, enhancing reusability.Example:Python# defining a function def a(): print( 3 min read User-Defined FunctionsPython User Defined FunctionsA User-Defined Function (UDF) is a function created by the user to perform specific tasks in a program. 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Although t 3 min read Keyword and Positional Argument in PythonPython provides different ways of passing the arguments during the function call from which we will explore keyword-only argument means passing the argument by using the parameter names during the function call.Types of argumentsKeyword-only argumentPositional-only argumentDifference between the Key 4 min read How to find the number of arguments in a Python function?Finding the number of arguments in a Python function means checking how many inputs a function takes. For example, in def my_function(a, b, c=10): pass, the total number of arguments is 3. Some methods also count special arguments like *args and **kwargs, while others only count fixed ones.Using ins 4 min read Default arguments in PythonPython allows function arguments to have default values. 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For example, if a function fun(a, 4 min read How to Pass Optional Parameters to a Function in PythonIn Python, functions can have optional parameters by assigning default values to some arguments. This allows users to call the function with or without those parameters, making the function more flexible. When an optional parameter is not provided, Python uses its default value. There are two primar 5 min read Return StatementsHow to Pass Optional Parameters to a Function in PythonIn Python, functions can have optional parameters by assigning default values to some arguments. This allows users to call the function with or without those parameters, making the function more flexible. When an optional parameter is not provided, Python uses its default value. There are two primar 5 min read Returning Multiple Values in PythonIn Python, we can return multiple values from a function. 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