i find when i use a new chrome browser in an new computer,
i download and install metaMask,when i input my password and my Mnemonic Phrase，then when i create new eth address.
Miraculous things come up.my new eth address is what I had created before.
what happened？
my private key is remembered by the metaMask？
Yes it is also safe but to be sure also take note of your private key so when you lost your pass phrase you have a back up .