General Notes

At the time of this writing, the following notes were the latest available from Apple's publicly accessible developer documentation. These type of notes can be subject to change.

  • Photos libraries are not backwards compatible. Once a library has been opened in El Capitan, you will not be able to open that same library from Photos, when running the app within Yosemite (10.10) or earlier.
  • Some services which require your Apple ID may request that you enable two-factor authentication. This type of authentication moves beyond a standard password, requiring additional authentication from another device. This is similar to security options made available by Paypal, Google, and others, where you verify a setting or login using a password and also a code sent to your cell phone, for example.

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