Binance Coin is nothing more than a digital currency. "Essentially, it's the underlying gasoline that powers the Binance ecosystem." This is how they are defined on the Binance website. If we look a little further and go to Binance's technical report, we see that BNB was contemplated since the creation of this exchange platform and their intention was only to obtain financing and offer benefits to the owners that operate on the same platform.
It has a total supply of 200 million coins and was created in order to encourage transactions on the exchange, through discounts to users who have BNB in their accounts from Binance. Like other cryptocurrencies, it is based on a decentralization technology that is organized under the blockchain architecture. In addition to providing benefits to its holders, BNB can also be used as a value transfer element on the Internet.
Binance Coin has a certain maximum offer, that is, it is not possible to issue more than a certain number of BNB coins. In its particular case, this max supply is established at 200 million from BNB. However, due to the 'coin burns' carried out by Binance, this number is now lower and equivalent to approximately 189 million BNB.
If you have good intuition, you have surely discovered that BNB does not work with mining. This cryptocurrency cannot be mined and instead uses a form of benefits for its holders. So it worked with a philosophy similar to the participation test.