A coin burn is when you take cryptocurrency, coins, or tokens and destroy them. In the case of Shib the tokens are put into a wallet called a burn wallet that nobody knows the pass phrases to. As of this writing about 41% of the overall supply of Shib has been burned. Shibburn.com is a great resource for up to date burn information. Over 9 billion tokens were burned 10/2021.
The rate of burning is expected to increase as our community is getting creative on ways to burn shib. As supply is lowered the inherent value of something increases. One of these creative ways to burn are if you buy an NFT Shiboshi and rename it over 3 million tokens are burned.
As you can see this make me very bullish on Shib. Start burning HERE.