> For the complete documentation index, see [llms.txt](https://docs.earn.polynomial.fi/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.earn.polynomial.fi/technical-implementation/approve.md). # Approve TL;DR:- Approvals are required because Polynomial uses the Ethereum blockchain to settle transactions. When using a Decentralized Application(dApp) like Polynomial, you must first approve each token you plan to deposit. Polynomial uses smart contracts on the Ethereum blockchain to execute transactions. To use a smart contract, you must : * Permit it to validate your token balance * Let it transfer the number of tokens you wish to trade from your wallet.