Brain Wallet is a type of crypto asset storage by memorizing the private key or seed phrase in your mind. To create a brain wallet, you can write the seed phrase on a piece of paper or notes, memorize it, and throw away the paper or delete the notes.
Storing crypto assets using a brain wallet has its advantages and disadvantages. Brain wallets are resistant to both online and offline attacks, making them attractive to those who are very concerned about security. However, if you forget your seed phrase or have any memory loss, you will lose access to your cryptocurrencies permanently.
Read also How to Safely Store Your Cryptocurrency.