Difference between uint, usint and int

Hi,

I understand the difference between a word, int and dint from the manual. But I have this sample project for modbus from Siemens and it contains uint and usint.

Any idea where I can find info on what they are? I'm guessing one of them is unsigned integer, but what would the other be?

uint : unsigned integer, 16bits (0-65535)

usint : unsigned short integer, 8bits (0-255)

Thanks, I forgot about short integers.