UIKit framework includes several classes whose purpose is to display text in a user's app, such as
UIWebView. Text views, created from the
UITextView class, are meant to display different types of text on screen.
UITextView is a powerful layout engine called Text Kit. Text Kit is built on top of Core Text, so it provides the same speed and power as that of Core Text.
UITextView is fully integrated with Text Kit; it provides editing and display capabilities that enable users to input text, specify formatting attributes, and view the results. The other Text Kit classes provide text storage and layout capabilities. The following diagram shows the position of Text Kit among other iOS text and graphic ...