We are advancing through our journey of building various real-world applications using Ruby. So far, we have explored the Adapter, Composite, and Decorator patterns independently. In this unit, we are going to apply these patterns to different scenarios to solve real-world problems.

Before we dive in, let's quickly recap the structural patterns we have learned so far:

1. Adapter Pattern: This pattern allows two incompatible interfaces to work together. We accomplish this by creating an adapter class that converts one interface to another.
2. Composite Pattern: This pattern helps us compose objects into tree structures to represent part-whole hierarchies. This approach allows clients to treat individual objects and compositions of objects uniformly.
3. Decorator Pattern: This pattern allows us to add new functionality to an object dynamically. We achieve this by creating a decorator class that wraps around the original object.

We will integrate all three structural patterns into different scenarios to solve real-world problems. Let's get started!

In this unit, we will integrate all three structural patterns into different scenarios to solve real-world problems. Let's have a quick recap of the scenarios we will be working on:

1. GUI Library-Related Tasks Using Decorator and Adapter Patterns: We will discuss how to apply the Decorator Pattern for enhancing UI components and the Adapter Pattern for interfacing different GUI elements.

2. Restaurant Menu with Decorator and Composite Patterns: We will simulate a restaurant menu where menu items can have multiple variations and compositions (e.g., combo meals), utilizing Ruby arrays and custom classes to structure this hierarchy.

3. Image Gallery with Adapter and Composite Patterns: We'll demonstrate how to handle different image formats through Adapter classes and represent a gallery structure using the Composite Pattern.

4. E-Commerce and Food Delivery Applications Using All Three Patterns: We'll explore how Ruby's powerful object-oriented features can be combined with patterns to create dynamic and flexible systems for e-commerce carts and food ordering interfaces, implementing all three structural patterns.

By the end of this unit, you'll be well-equipped to use structural patterns in your Ruby projects effectively. Let's dive in!