In Program, The variable declarations are initialised by character type is suitable to all situation.    That is, the character type variable having much flexible level, to solve all type inputs are accepted.

 for example,

type I

a=0     //Numeric type variable declaration

When you are call the variable 'a' for assign numeric input, it will allow to type any numeric, but it will not allow even  a single blank space('   ' ). 

suppose if your declare a variable with character type

 type II

a=space(20)
(or)
a="                                                         "

If you  are call the variable ' a' for assign any type of input like numeric or character.
It will allow multiple support character or alphanumeric or numeric.

Conclusion:

Character type of declaration is better in code development.