What is byte type that is used rfid code

I am doing a project on rfid system. While analyzing some old codes there is datatype named as “byte” which was type of previous mbed os versions. I don’t know what to do. My code is stuck.

Hello,

try to place this to header file

typedef unsigned char byte;

BR, Jan

Using this, won’t generate any error or warning, right…?
Also it won’t change the working of the code, right.?