Functions are blocks of code that perform specific tasks and can be called whenever needed. They are defined using the def keyword followed by a name and parameters, and can contain lines of code and a return expression. There are two types of functions: built-in functions that are pre-defined in Python like len() and print(), and user-defined functions that are created by programmers using def and can be called anywhere in the code.

1. Functions
Functions are the block of statement which
executes and perform specific task
whenever it is called.
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Functions are just like a packet in which we
pack the lines of code inside it and use it
whenever we need.

2. Syntax:-
def function_name(Parameters):
function_body(lines of Code)
return expression

3. Types of Function:-
1.Built-In Functions.
2. User-Defined Functions.

4. Built-In Functions:-
Built-in Functions are those functions
which are already pre-coded and defined
in Python.
For ex:-
len(), min(), max(), print(), type(), etc.

5. User-Defined Functions:-
Functions which are defined by the programmer at the
time of writing code are known as User-Defined
Functions.
User-Define Functions can be define using def keyword
written before the Function Name.
For ex:-
def function_name():
function_body

6. Thank You!!!