Why can I add characters to strings but not characters to characters?

Question

So I wanted to add a character to a string, and in some cases wanted to double that characters then add it to a string (i.e. add to it itself first). I tried this as shown b

Answer 1

String string = "" + X + X;

is an example of concatenation. By pre-pending the empty string you specify that the result should be a string. The first line of code tells the compiler that you are adding 2 chars (or ints) which should result in an int, and not a string.