What more does the complexity of TextEditingController gives us than the simple TextField?

"A more powerful, but more elaborate approach, is to supply a [TextEditingController](https://api.flutter.dev/flutter/widgets/TextEditingController-class.html) as the [controller](https://api.flutter.dev/flutter/material/TextField/controller.html) property of the TextField or a TextFormField."

OK, maybe but why and what more does the complexity of TextEditingController gives us than the simple TextField?

Start with the linked TextEditingController API documentation and the TextField controller property documentation, then review the quoted explanation. Clarify what capabilities a TextEditingController provides beyond a simple TextField, and consider the work done when the documentation answers the reader’s question directly.

Written by the indexing model from the issue text.