Welcome back to our exploration of Object-Oriented Programming (OOP) in TypeScript. This unit's topic is Inheritance, a feature that can significantly enhance code reusability and efficiency.

Programming, especially OOP, often mirrors concepts found in the real world. Inheritance is one such trait - Child classes inherit characteristics from their Parent classes, akin to genetics in biology.

Here is a concrete TypeScript demonstration of a Child class inheriting from a Parent class:

In this instance, the Child class inherits from the Parent class, thereby sharing the greet() method. This is inheritance in action!