What does the switch on the microphone do?

This is a standard switch that anyone can use! You may often see it in karaoke.
The on/off switch is mainly used on dynamic microphones.
You can easily turn it on and off with your fingertips.

I have the impression that many microphones used with PA equipment do not have this switch. This is to prevent the speaker from accidentally turning off the switch.

If you are looking for a microphone for yourself to use for speaking, one with an On/Off switch is easier to use.

Please see the following blog for a detailed explanation of this.

⇒ [Acoustic Tips] How to make good use of the Shure SM58, a standard microphone in PA systems

This switch is often seen on condenser microphones.
Microphones have polar patterns and some microphones have a switch for selectable polar patterns.
Select the appropriate one for your recording environment.

Ex.) C414
From left to right: omnidirectional, wide cardioid, cardioid, supercardioid, and figure eight.

Ex.) BY-PM700
Selectable polar patterns are often included in USB microphones.

A pad switch is a switch used to attenuate the level of the input signal to prevent clipping. In other words, this functions as the attenuator. You may often see this function on mixers.
If the sound is clipped and distorted, there is nothing more you can do after recording, so it’s better to turn on the pad switch when recording a loud sound.
However, as with any switch, it is recommended that you actually listen and decide on the appropriate setting.

Ex.) C414
You can select the attenuation level.

Ex.) SR-VM4
Often used in shotgun microphones. This model not only has an attenuator but also a +20 booster.

A low-cut switch cuts sound below a certain frequency.
By cutting low frequency, it suppresses environmental noise mainly caused by air conditioning and vibration noise coming from the floor.
This is a great feature for those who record at home and have difficulty setting up a recording environment!
It may be safer to turn a low-cut switch on for recording outside of a recording studio.

Ex.) C414
As with the pad switch, there are several levels to choose from.
C414 can be switched finely among them.

Ex.) C-2
The top is flat and the middle is low cut. In many cases, there is no indication of the Hz value, but only these symbols.

This is a midrange boost switch.
The main vocals are often boosted in the midrange to make it the key point of the piece by highlighting it in the mix. Boosting the mid basically makes it easier to listen to the vocals.