ABSTRACT
One of the main features of Fortran is the portability of source code. When a variable or a constant is declared, the compiler allocates storage locations for the variable or the constant with the default processor-dependent range and precision. Fortran allows the programmer to specify the precision and the range of a variable through the kind attribute. The precision of a real number is a measure of exactness of the number. It is specified in terms of the number of digits that are used to express the number reliably. When a real number is stored in a computer, the number of bits used for the fractional part determines the precision of the number. Though real numbers are stored as binary digits, precision is expressed both in binary as well as in decimal form. The complex declaration with a proper kind is required to declare a double complex variable.
