Hey there!

You've already seen a few built-in functions, such as:

• int 
• str 
• sum 
• print 
• range 

Built-in functions are just some that come with Python. We can use them anywhere in our programs without defining them or telling Python where they come from.

There's quite a few built-in functions that we can use—and they do a variety of things. Here's a few more examples:

• len(my_list)  gives you the length of the list my_list —it also works with tuples and strings;
• max(my_list)  gives you the maximum number in my_list  (there's also min(my_list) )
• round(my_decimal)  rounds my_decimal  according to maths rules (e.g. 3.5 gets rounded up to 4; 3.49 gets rounded down to 3)

There's more, and we'll be introducing some of them as we go through the course.

Always feel free to check the official documentation for more info about built-in functions!

Kind regards,

—Jose and the Teclado team