When searching for pattern matches in the data strings on the RS232/Serial line, this character can be used to stand in for any character or group of characters.
For example, let's say you use Fire*
That would tell the GetSerial module to recognize any instance of the word Fire, regardless of whether there are any characters after the word. So, it would recognize Fire or Fired or Fires but it would also recognize the Fire in Fire Sale or Fire Department.
As another example, let's say you use *age*
That would tell GetSerial to recognize any reference to the three letters age close to each other, regardless of whether that was in the word PageGate or NotePage or ageless or damage. Any instance of the three characters together will be recognized.