What Is A Keystore File (UTC)?
A keystore file is a password-encrypted file which contains your private key on the Ethereum network. Your private key is used to sign transactions when sending crypto assets from your address. Because both the keystore file and a password are required to unlock access to your Ethereum address, this adds an additional layer of security as both file and password are required together. If someone gains a copy of your file but does not have the password, your funds are still secure, as opposed to your naked private key stored in a plain text file.