Answer 1

If the names you are referring to are modules, then my answer is:

For example, imagine you are trying to make a program that will print the current date and time. Well, someone already wrote code to do that and packet it in a module called time.
So, to take advantage of that module you can import it into your code and use it. Here is an example:

import time # here is how you import the module
cur_date_time = time.ctime() # ctime is a function of time module
print(cur_date_time)

Hope I helped.