The second factor.
WHAT AN AUTHENTICATION APPLICATION DOES
Generates time-based codes for signing in.
WHY IT IS BETTER THAN CODES BY MESSAGE
Message-based codes can be intercepted or redirected.
WHAT TO SET UP
An authentication application, for every account that supports it.
WHAT TO DO WHEN SETTING ONE UP
Save the recovery codes the service provides.
WHERE TO KEEP THEM
Somewhere separate from the phone.
WHY
If the phone is lost, the codes are what get you back in.
WHAT HAPPENS WITHOUT THEM
You are locked out, and recovery may be impossible.
WHAT TO TEST
Signing into an important account, and confirming you could recover without the phone.
WHAT TO NEVER DO
Share a code with anyone, however they identify themselves.
WHY
A code is for you alone. Anyone asking is taking your account.
WHAT TO BE CAREFUL WITH
Codes visible on a locked screen The phone being shared with others
WHAT TO KEEP EXCLUSIVE
The device holding your authentication application.
WHAT TO DO WHEN CHANGING PHONE
Transfer it deliberately, before wiping the old one.
