Can some body please explain me the following two terms ? 1)signed two's-complement integers 2)16-bit unsigned integers representing Unicode characters Thanx in advance

signed: byte ---> -128 to +127 unsigned char ---> 0 to +65535 ------------------------------------------------- the two's complement: (working with bytes) decimal binary 4 ---- 00000100 -4 ---- 11111100 how did I find that -4 was 11111100?? 1)invert all bits: 00000100 becomes 11111011 2)add another bit to the end 11111011 + 1 --> 11111100