# Gas and Fees Learn about the differences between `Gas` and `Fees` in Ethereum and Cosmos. {synopsis} ## Introduction to `Gas` in the SDK ## Matching EVM Gas consumption ## Gas refunds ## AnteHandler The `AnteHandler` is a special `handler` that is run for every transaction during `CheckTx` and `DeliverTx`, before the `handler` of each `message` in the transaction. `AnteHandler`s have a different signature than `handler`s ## Next {hide} Learn about the [encoding](./../core/encoding.md) formats used on Ethermint {hide}