It is probably a condenser electret. If you look closely-- hopefully it has only two pins-- one of the pins is connected to the case-- that is the ground. The other gets connected to Vcc through a resistor, the output through a cap. Schematics are cheap and plentiful on the web.
Microphones like many other componets have largely varing specifications.
If you mean the frequency response, I would venture to say it at least covers the human voice spectrum which is close to 300Hz to 3000Hz, although it can go higher. I have found this type of microphone with a frequency response to greater than 20Khz.