In this Delphi programming tutorial we start with an application that loads and saves some settings out of an ini-file. We then tidy up the code a bit by creating a new class inheriting from TIniFile that uses properties with getter and setter methods to change the settings rather than ReadString / WriteString. This makes the code much nicer as you get code completion and error insight. We also make use of the Initialization and Finalization sections of a unit to create and free our new class. This video is 10 minutes long and you can watch it here.
This book will make you a faster Delphi developer, it doesn't matter if you are just starting out, or have been using Delphi since version 1, you will find all sorts of tips, tricks and hacks to boost your productivity.