Views are the building block of iOS interfaces. Views display graphics and information to the end user and are their design is managed in a variety of ways.
UIView provides a structure for drawing and handling events. A UIView object claims a rectangular region of its enclosing superview (its parent in the view hierarchy) and is responsible for all drawing in that region, as well as receiving events that occur in the region. [Xcode Tooltips]
This section will cover the following chapters
The above examples shows an exploded representation of a view heirarchy which is discussed here. Working with Views
Although each section has its own references, a good starting point would be: