Multi-factor authentication
Multi-factor authentication means using two or more different factors to prove who you are: something you know, something you have or something you are.
A password is something you know. A code on your phone is something you have. A fingerprint is something you are.
Why it matters for a small business
If one factor is stolen, the others still stand in the way. Turn it on for your email and your business accounts.
Source: NIST CSRC glossary
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