Example
var s = "Hello"; // The string referenced by variable 's' is normally immutable, but
// since it is memory, we could change it if we can access it in an
// unsafe way.
unsafe // allows writing to memory; methods on System.String don't allow this
{
fixed (char* c = s) // get pointer to string originally stored in read only memory
for (int i = 0; i < s.Length; i++)
c[i] = 'a'; // change data in memory allocated for original string "Hello"
}
Console.WriteLine(s); // The variable 's' still refers to the same System.String
// value in memory, but the contents at that location were
// changed by the unsafe write above.
// Displays: "aaaaa"