A function is a reusable block of code designed to perform a specific task. Functions help break down complex problems into smaller, more manageable parts. They allow programmers to write cleaner, more organized, and more efficient code by enabling code reuse and abstraction.
In Python, a function is defined using the `def` keyword, followed by the function name and parentheses which may include parameters. The code block within every function starts with a colon (:) and is indented.
Here is an example of a simple function in Python:
def greet(name):
print(f"Hello, {name}!")In this function, ‘name’ is a parameter – a placeholder for the data that the function will operate on. When the function is called, we provide an actual value, known as an argument.
The main differences between parameters and arguments in the context of functions are as follows:
Parameters
These are the variables that are declared in a function definition. Parameters act as placeholders for the values that a function can accept. When defining a function, you specify parameters in the parenthesis following the function name. They represent the kind of data that the function expects to receive when it is called.
Arguments
These are the actual values or data that you pass into the function when you call it. An argument can be any object – a number, a string, a list, another function.
Here is how you would call the previously defined ‘greet’ function with an argument:
greet("Alice")In this example, “Alice” is the argument passed to the function ‘greet’. The parameter ‘name’ within the function takes on the value of the argument “Alice”, and the function proceeds to execute its code block with this value, printing “Hello, Alice!” to the console.