S tring :- String is a collection of character type data. In other words character arrays are called string. In C programming the group of characters,digits, and symbols enclosed within quotation marks are called as string.Every string is terminated with string ‘\0’(NULL) character. The Null character is a byte with all bits at logic zero. Hence its decimal value is zero. It is not compulsory to write ‘\0’ in string. The compiler automatically puts ‘\0’ at the end of the character array(string). Every character of string store in contiguous memory locations. Each   character of string occupies 1 byte of memory.   char nm[5];   A      B      H       I      \0    nm[0]           nm[1]           ...