Update index.md

Author: Dexaran

src/content/developers/docs/standards/tokens/index.md

@@ -19,6 +19,7 @@ Many Ethereum development standards focus on token interfaces. These standards h
 Here are some of the most popular token standards on Ethereum:
 
 - [ERC-20](/developers/docs/standards/tokens/erc-20/) - A standard interface for fungible (interchangeable) tokens, like voting tokens, staking tokens or virtual currencies.
+- [ERC-223](/developers/docs/standards/tokens/erc-223/) - A fungible token standard with "transaction handling" model that makes token behave identical to ether.
 - [ERC-721](/developers/docs/standards/tokens/erc-721/) - A standard interface for non-fungible tokens, like a deed for artwork or a song.
 - [ERC-777](/developers/docs/standards/tokens/erc-777/) - ERC-777 allows people to build extra functionality on top of tokens such as a mixer contract for improved transaction privacy or an emergency recover function to bail you out if you lose your private keys.
 - [ERC-1155](/developers/docs/standards/tokens/erc-1155/) - ERC-1155 allows for more efficient trades and bundling of transactions – thus saving costs. This token standard allows for creating both utility tokens (such as $BNB or $BAT) and Non-Fungible Tokens like CryptoPunks.