What is the purpose of the automatic interface markup system in application development?

The Auto Layout system in iOS is designed to create adaptive user interfaces that display correctly on different devices and orientations.

It allows you to set rules (constraints) describing the relative positioning and sizes of interface elements, instead of fixed values. This simplifies support for various screen sizes, localizations, and dynamic interface changes.

For example, you can specify that a button should always be centered on the screen and have margins from the edges, and Auto Layout will automatically calculate its position and size when the window size or device orientation changes.