Two-factor authentication now rolling out to Instagram users
With the new two-factor authentication, signing into Instagram means using a one-time code that is texted to you
The bottom line is that in addition to your password and username, someone trying to gain access to your Instagram account without your permission will not only have to get your phone number, they will have to get your phone. The two-factor authentication will protect your Instagram account from a hacker that could take down your pictures, attack your friends and family, and possibly cost you your job.
source: TechCrunch
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