Python question When reading and writing into a file. Say i want to read ininput using a file called

Python question When reading and writing into a file. Say i want to read ininput using a file called input.txt and then do something. Then iwant to output the results to an additional file called output.txt.i have seen ouput.out or results.out used and not .txt. What is thedifference? When would you use .out and not .txt? thank you Attached