On the right side of the iPad are two switches. Near the top is the side-switch and below that is the volume switch.
The volume switch
The volume switch is an up/down combo switch. This switch is used to adjust the audio volume of the iPad. Press the upper side of the switch to increase the volume. And press the lower side of the button to decrease the volume. To mute the volume, press and hold down the lower side of the volume button until the volume goes to zero.
The side switch
The side switch has two positions that can be slid in the up position or in the down position. When it is in that down position, it will show a red dot.
By default, this switch is used to mute sound effects and notifications by having it in the down position (with the red dot showing). It does not mute audio playback (as some people might think).
However, the function of this switch can be customized by going to “Settings -> General”
As seen in the above screenshot, the side switch functionality can be set to either “Lock Rotation” or “Mute”. As mentioned, it is set to mute notifications by default.
But if you set it to “Lock Rotation”, then the display on your iPad will not automatically rotate as you rotate the device when the side switch is in the down position. Switch to up position to allow display rotation again.