What does it mean that safe space layout guide is backwards deployable?

What does it mean in WWDC 2017 Auto Layout Techniques in Interface Builder that Safe Space layout guide is backwards deployable?

Answered by ManuelMB in 269003022

This means you can switch to using the safe area layout guide in Interface Builder even if you still target iOS 10 and older.

Accepted Answer

This means you can switch to using the safe area layout guide in Interface Builder even if you still target iOS 10 and older.

Ok. Thanks.

What does it mean that safe space layout guide is backwards deployable?
 
 
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