in Delphi OOP
:: A feature of the Delphi language added some years ago (way back in in Delphi 2005) called "Class Helpers" is designed to let you add new functionality to an existing class (or a record) by introducing new methods to the class (record). In simple words, a class helper is a construct that extends a class by introducing new methods in the helper class. A class helper allows you to extend existing class without actually modifying it or inheriting from it.
Read the full article to learn What Class/Record Helpers Are, When To Use and When Not To Use