The HBD Stabilizer is a trading bot that operates on Hive's Internal Exchange. It was created in 2021 by 
It is repeatedly funded by the community approval of a proposal made to the Decentralized Hive Fund. Each day, HBD is allocated to the bot that places limit orders on both the buy and sell side.
The goal is the HBD Stabilizer is to help keep the price of HBD pegged. This coin is backed by $1 worth of $HIVE. When the price of HBD gets too low (below the peg), the bot buys HBD. By the same token, when the price of the coin is above the $1 peg, it will sell HIVE.
For this reason, the price of HBD tends to maintain the peg better than the prices on the centralized exchanges.