Starting today, Instagram will begin putting new and existing users under the age of 18 into “Teen Accounts” — a move that will affect how tens of millions of teens interact with the platform. The new account type automatically applies a set of protections to young users, and only users 16 years of age and older can loosen some of these settings.

For starters, the accounts of all minors on Instagram will be private by default (not just teens under 16) and will come with some of…