Built-in functions in Python are pre-defined functions readily available for use in any Python program without requiring additional specifications or definitions. One of the built-in functions is the print() function - we have already used it. We didn't need to define this function, write its body and specify the return value - we just called it and provided inputs. There are many built-in functions in Python. Now we will consider the most commonly used:

print(): Outputs a specified message or variable to the console:

len(): Returns the length (number of elements) of an object, such as a string, list, or tuple:

sum(): Calculates the sum of a sequence of numbers:

max() and min(): Returns the maximum/ minimum value from a sequence:

You may have already been familiar with these functions before, or maybe not. The key in this section is to see the difference between built-in functions and your own.