Constant Pointers and Pointers to Constants

Give  a look at
http://www.codeguru.com/cpp/cpp/cpp_mfc/general/article.php/c6967

Constant Pointers: The pointer itself is constant and cannot be changed to point to anything else but the object being pointer to can be modified

Pointers to Constants: The object being pointer to is constant and cannot be modified, but the pointer can

You can also have Constant Pointers pointing to Constants, which means neither the pointer nor the object it points to can be modified.

some example please to better understand

// how to declare a pointer to a constant character
const char * myPtr = &char_A;

// how to declare a constant pointer to a character.
char * const myPtr = &char_A;

// how to declare a constant pointer to a constant character.
const char * const myPtr = &char_A;