A format specifier is a sequence formed by an initial percentage sign (%)
indicates a format specifier, which is used to specify the type and format of
the data to be retrieved from the stream and stored into the locations pointed
by the additional arguments. In short it tell us which type of data to store
and which type of data to print.
The format specifier is used during input and output. It is a way to tell the
compiler what type of data is in a variable during taking input using scanf()
or printing using printf(). Some examples are %c, %d, %f, etc.
The format specifier in printf() and scanf() are mostly the same but there is
some difference