Types of Microphonesby drumdoctor
The terms Omni-directional---uni-directional---
cardioid--& super cardiod refer to the polar pattern.
Basically--if you are looking at the microphone as it is laying on it's side,the ploar pattern shows how tight the pattern is and how much unwanted sound is rejected.
The super cardioid is the tightest and the cardioid is next.
Some of the cardioids are very close in pattern to the supercardioid mics.
If you are a vocalist and are concerned about quality,then I recommend the following mics:
1---Samson CO5 CL--Cardioid-condenser--40-16k--about $70. This is the best bang for the buck