I will describe separately, although this is a special case.
When shooting at night, an inexperienced photographer https://www.artlook.us/service/wedding-photo-booths-nyc/ is forced to raise the ISO to provide a fast shutter speed for handheld shooting.
Raising the ISO leads to an increase in the amount of digital noise, and the worse the camera matrix, the more noise will be in the final frame.
How to avoid it?
Use low ISO shooting and a tripod to shoot. Using a built-in or remote flash can also help.
The quality of pictures taken using the built-in flash will be terrible. But the description of these passions is beyond the scope of this article.