Some definitions

Byte Angle
This is a value between 0 and 255 representing a direction and is used with some line specials. Some useful values are:
96
Northwest
64
North
32
Northeast
128
West
  0
East
224
Southeast
192
South
160
Southwest
Tic
A time interval of 1/35 second. There are 35 tics in one second.
Octic
A time interval of 1/8 second. There are 8 octics in one second. (This may not be the same as Hexen, since the Hexen specs weren't clear on this.)