Donuts are a form of community currency started in January 2019 on the r/ethtrader subreddit, which is a Reddit community focused on Ethereum trading and related topics. Donuts are ERC-20 tokens on the Ethereum blockchain and serve as a way to reward and incentivize positive contributions and engagement within the r/ethtrader community.
Users on r/ethtrader can earn Donuts based on their contributions, including posting quality content, making insightful comments, and receiving upvotes from other community members. These Donuts can then be used within the subreddit for various purposes, such as voting in polls, participating in governance decisions, and even exchanging them for other cryptocurrencies.