Whether it's barracking for your sports team or delivering a karate chop, there's something satisfying about letting out a good yell.
When you do, interesting things happen.
Screaming is not good for the small flaps of flesh we call the vocal folds. They clap together violently and the sound you make is distorted and, if you yell too much, they can swell which will make it harder for them to function properly.
The world record for the loudest yell is from Irish teacher Annalisa Flanagan, who measured 121 decibels.
It's hard to comprehend just how loud that is, but it's like standing next to an angle grinder or a jet plane taking off. In other words - it's seriously loud and enough to permanently damage your hearing.
Your ears have a trick to protect your hearing from loud noises and, curiously, it also quietens your own voice a little.
The tensor tympani and the stapedius are two of the smallest muscles connected to the two smallest bones in your body. These are in your middle ear and their job is to clamp down on the bones to reduce the noise that goes into your inner ear (the cochlear).
We need them because our hearing has to cope with a huge range of sound levels. One moment all is quiet, and the loudest sound is a bird in the distance. At about one decibel, that's very faint and on the limit of normal hearing.
Then you step inside where the rock band is in full swing and you're blasted with 110 decibels.
That might not seem like much, but it's a vast difference in loudness. The decibel scale is a doubling every 10db, so that means the rock concert is 100,000,000,000 times louder.
It's hard to get your head around this scale, but if the end of your thumb is 2cm long, the equivalent distance would be 500,000 kilometres.
The softest sounds are only just strong enough to move the eardrum by the width of an atom, while the loudest sounds will flatten the hair cells in your inner ear.
If you're talking to a person who has poor hearing, it can be tempting to talk really loudly or maybe even shout.
Unfortunately, that also distorts the sound, which makes it worse.
It's upsetting for both you and them. A much better way is to stand where the person can see you and read your lips.
Speaking with a strong, clear voice helps too.
And there's no. Need. To. Talk. On. The. Moon. Because that sounds really silly.
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