Question about Scanf options

Question

What is the difference between scanf("%*f") and not writing it at all? and when do we use each one of them ? Thank you

Answer 1

This means that there is a float in your input stream but you do not care about it in your program. It can be useful to handle files of predefined format in which all data is not useful or when you use the same file for multiple programs and all of them do not need the same information