Hi Yifei,
We use "Absence / Attendance type" in time management module (PT) but Wage type is for payroll(PY).
To see what absence / attendance types are, have a look at T554S. Open it by SM30 and for wage types see V_512W_O.
If you look for time types you should look at V_T555A.
In fact we define time types to keep time amounts into like overtime, worktime, absence time, attendance time and so on but absence / attendance types use for request.
If EE send an hourly absence from 8:00 to 10:00 you can count it into a time type to have sum of hourly absences for example. Or you can import absence records directly into payroll without keeping it into any time type.
Regards,
Omid