Resource Credits (RCs) on the Hive blockchain are a key part of it´s infrastructure. They are an internal, rechargeable currency required to pay for transaction costs. As the transactions on Hive are feeless, the resource credits prevent spam attacks.
RCs are automatically allocated to a user account based on the amount of Hive the account has staked, i.e. how much Hive Power (HP) it has. The more HP an account has, the more RCs it can generate.
For each transaction on Hive a specific amount of RCs is consumed (the value varies slightly dependent on network bandwidth). If an account runs low on RCs, it cannot perform certain transactions any further. But the RCs self-replenish at a rate of 20% per 24 hours|Reference: https://hive.io/whitepaper.pdf and after 5 days go back up to 100% (similar to the voting mana).
Different types of transaction (e.g. posting, upvoting, transferring tokens, etc.) require a different amount of RCs. Some require very little RCs (e.g. claiming rewards and upvoting require less than 0,05 HP equivalents), some require a lot of RCs (e.g. claiming a single account creating token requires 7000 to 9000 HP equivalents).
Overview about how much RC are required per transaction type: https://hivehub.dev/stats?metric=rc&timeframe=daily
