First proposed in BIP39, a Mnemonic is a form of cleartext private key that is intended to help users memorize and transcribe complex private keys. A Mnemonic generally consists of 12, 15, 18, or 21 words, which are taken from a fixed word pool and whose generation sequence is based on a particular algorithm. Therefore, there is no need to worry that an address would be generated from random entering of 12 words. Anybody who steals your Mnemonic can steal all your funds immediately. Therefore, users should pay attention to the following during Mnemonic backup:
- Back up your Mnemonic using a physical medium. For example, you can write it down on paper. Never store its snapshot or photo on a device with online access, to prevent theft by hackers.
- Verify that the backed-up Mnemonic is correct. Once one or two words are wrong, it is especially difficult to recover the correct Mnemonic later.
- Please properly keep the backed-up Mnemonic. Making multiple backups is strongly recommended, to guard against theft or loss.