• Passphrase, also known as a "25th word," is a smart addition to a seed phrase because it adds an extra layer of security to your cryptocurrency wallet. With Most hardware wallets the passphrase can be a word, a phrase or a sentence. Our cold wallets have room for whichever you choose.

• Seed phrase is a series of words that serve as a backup for your private key, which is necessary to access and control your cryptocurrency holdings. If someone gains access to your seed phrase, they can easily take control of your wallet and steal your cryptocurrency.

By adding a passphrase, you are essentially adding another layer of security that must be unlocked before anyone can access your wallet. Even if someone has your seed phrase, they will not be able to access your wallet without the correct passphrase. This is because a passphrase is used to create a "hidden" wallet within your main wallet, so you have two layers of protection instead of just one.

A passphrase can be any string of characters, a word, or a sentence (hardware wallet technology specific) that you choose, but it is important to choose a strong, unique passphrase that is not easily guessable or discoverable. You should also make sure to remember your passphrase or store it in a secure location, as it cannot be recovered or reset if it is lost.