About the Buttons on the Left Side of the IPhone 7

Volume controls

Volume controls buttons iPhone
When you’re on the phone or listening to songs, movies, or other media, the buttons on the side of iPhone adjust the audio volume. Otherwise, the buttons control the volume for the ringer, alerts, and other sound effects.

Lock the ringer and alert volumes. Go to Settings > Sounds, then turn off Change with Buttons. To limit the volume for music and videos, go to Settings > Music > Volume Limit.

Use Control Center to adjust the volume. When iPhone is locked or when you’re using another app, swipe up from the bottom edge of the screen to open Control Center.

You can also use either volume button to take a picture or record a video.

Ring/Silent switch

Flip the Ring/Silent switch to put iPhone in ring mode or silent mode.

 

Ring/Silent button iphone
In ring mode, iPhone plays all sounds. In silent mode, iPhone doesn’t ring or play alerts and other sound effects (but iPhone may still vibrate).

Important 
Silent modeClock alarms, audio apps such as Music, and many games play sounds through the built-in speaker, even when iPhone is in silent mode.
Use Do Not DisturbYou can also silence calls, alerts, and notifications using Do Not
Disturb. Swipe up from the bottom edge of the screen to open Control Center, then tap symbol of the moon.