1. Microphones and their Pickup patterns.

2. Cardioid Microphone.
A cardioid microphone has the most sensitivity at the front and is least sensitive at the back.
They are useful for loud stages because of their ability to isolate unwanted ambient sound and resistance to feedback.
The pattern looks like a heart on the polar response chart, hence the name, cardioid.
Cardioid is mostly used for live sound, it can be pointed away from the sounds you do not want.
It is the most important microphone for recording, it can record exactly what you want it to.

3. Omnidirectional microphone.
An omnidirectional microphone picks up the sounds equally from above and below, front and back.
These microphones usually have a flat response, this is perfect if you want to record everything in the room or you do not want the sound to change with location of the source.
Omni mics are mostly at “on location” TV interviews used by the news. They are also for inexperienced users because the sound is equally picked up in all directions.
There is no proximity effect with an Omni so you do not have bass boost changing the sound of the source.

4. Hyper-cardioid microphones.
Hyper-cardioid mics have higher directionality and rejection of sound coming the sides than cardioids but slightly more pickup bass from behind.
They are useful for isolating the wanted sounds from the front and rejecting unwanted and ambient sounds from the back and side.
Side to side movements can put a performer in and out of the pattern very quickly and cause significant problems for the sound system operator.
The pattern is most useful in stable, non moving sources for live sound.

5. Figure of eight microphones.
Figure of eight microphones pick up sound behind and in front, they are most common with ribbon microphones.
In the early days of radio, it was used for live performances to pick up the live audience and the performer simultaneously,. Or two people sitting at a table facing each-other.
Not useful for live sound, this pattern is most useful in advanced recording techniques called Mid/Side. There is no proximity effect with a bi-directional microphone.

6. Microphone pickup patterns.
Figure of eight microphone pattern.
Omnidirectional Microphone pattern.
Hyper-Cardioid microphone pattern.
Cardioid microphone pattern.

7. References.
"Pick Up Patterns - Heil Sound Pro". Heilsound.com. N.p., Web. 18 Oct
Chapters, The et al. "Microphone Polar Patterns: Cardioid, Omnidirectional, Figure-8". E-Home Recording Studio. N.p., Web. 18 Oct