We can't find a person alive , without doing knuckle cracking.Everybody
loves to hear the sound of knuckle-cracking.
How do your knuckles makes sound?
All the joints in our body is surrounded by a thick, clear liquid called synovial fluid.
When you try to stretch or bend your finger to crack your knuckles, a gas in the synovial fluid escapes and turns into a bubble which then burst and produces the popping sound in your knuckles and other joints like toes,knees,neck etc.
Cracking your joints will stimulates your tendons and relaxes your muscles.
There is a popular belief that knuckles cracking will lead to arthritis.Cracking your knuckles will not hurt your bones or cause arthritis.Too much of knuckle cracking may cause tissue damage in the affected joints.
Once if you crack your joints,you can't do it for another 25-30 minutes until the gas gets reabsorbed into the synovial fluid.