# 3.29 Unicode RTLO

There is a security pitfall that arises because of the use of the Unicode Right-to-Left-Override control character (`U+202E`) in `Solidity` smart contracts causes the text to be rendered from right to left instead of the usual left to right.

This reverse rendering confuses the users as well as the security reviewers from understanding what the real intent is of that particular snippet of the smart contract.

The best practice here is to ensure that such confusing Unicode characters (the RTLO control character) is not used within smart contracts at all.


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