byte + byte = int… why?

Question

Looking at this C# code:

byte x = 1;
byte y = 2;
byte z = x + y; // ERROR: Cannot implicitly convert type \'int\' to \'byte\'

The result of

Answer 1

From the C# language spec 1.6.7.5 7.2.6.2 Binary numeric promotions it converts both operands to int if it can't fit it into several other categories. My guess is they didn't overload the + operator to take byte as a parameter but want it to act somewhat normally so they just use the int data type.

C# language Spec