every function you create will provide similar pattern of usage you type the function namean open parenthesisany required inputand close parenthesisthen you press enter in this caseyou have no inputso all you type is helloas the progressesyou see other examples for which input is required sending information to functions the firstfunction py example is nice because you don' have to keep typing that long string every time you want to say hello(howeverit' also quite limited because you can use it to say only one thing functions should be flexible and allow you to do more than just one thing otherwiseyou end up writing lot of functions that vary by the data they use rather than the functionality they provide using arguments helps you create functions that are flexible and can use wealth of data understanding arguments the term argument doesn' mean that you're going to have fight with the functionit means that you supply information to the function to use in processing request perhaps better word for it would be inputbut the term input has been used for so many other purposes that developers decided to use something bit differentargument although the purpose of an argument might not be clear from its nameunderstanding what it does is relatively straightforward an argument makes it possible for you to send data to the function so that the function can use it when performing task using arguments makes your function more flexible the hello(function is currently inflexible because it prints just one string adding an argument to the function can make it lot more flexible because you can send strings to the function to say anything you want to see how arguments workcreate new function in the python shell window (or open the arguments py file of the downloadable sourcesee the introduction for the urlthis version of hello()hello ()requires an argumentdef hello greeting )print(greetingnotice that the parentheses are no longer empty they contain wordgreetingwhich is the argument for hello (the greeting argument is actually variable that you can pass to print(in order to see it onscreen sending required arguments you have new functionhello (this function requires that you provide an argument to use it at leastthat' what you've heard so far type hello and press enter in the python shell window you see an error messageas shown in figure - telling you that hello (requires an argument