What is the content compression resistance and content hugging of a UIView?

What is the content compression resistance and content hugging of a UIView? How do these relate to the intrinsic content size of a view?

Taken from objc.io's excellent Advanced Auto Layout Toolbox article:

> Intrinsic Content Size > > The intrinsic content size is the size a view prefers to have for a specific content it displays. For example, UILabel has a preferred height based on the font, and a preferred width based on the font and the text it displays. A UIProgressView only has a preferred height based on its artwork, but no preferred width. A plain UIView has neither a preferred width nor a preferred height. > > Compression Resistance and Content Hugging > > Each view has content > compression resistance priorities and content hugging priorities > assigned for both dimensions. These properties only take effect for > views which define an intrinsic content size, otherwise there is no > content size defined that could resist compression or be hugged. > > Behind the scenes, the intrinsic content size and these priority > values get translated into constraints. For a label with an intrinsic > content size of { 100, 30 }, horizontal/vertical compression > resistance priority of 750, and horizontal/vertical content hugging > priority of 250, four constraints will be generated: > > H:[label(<=100@250)] > H:[label(>=100@750)] > V:[label(<=30@250)] > V:[label(>=30@750)] > > If you’re not familiar with the visual format language for the > constraints used above, you can read up about it in Apple’s > documentation. Keeping in mind that these additional constraints are > generated implicitly helps to understand Auto Layout’s behavior and to > make better sense of its error messages.

Here's another StackOverflow question that addresses the difference between content compression resistance & content hugging: https://stackoverflow.com/questions/15850417/cocoa-autolayout-content-hugging-vs-content-compression-resistance-priority