Added text for structural design patterns.

README.md

@@ -313,7 +313,35 @@ entities.
 
 ### 🔌 Adapter
 
-#### Overview
+Real world example:
+
+> Consider that you have some pictures in your memory card and you need to
+transfer them to your computer. In order to transfer them you need some kind of
+adapter that is compatible with your computer ports so that you can attach
+memory card to your computer. In this case card reader is an adapter.
+
+Another real world example:
+
+> Another example would be the famous power adapter; a three legged plug can't
+be connected to a two pronged outlet, it needs to use a power adapter that makes
+it compatible with the two pronged outlet.
+
+And another:
+
+> Yet another example would be a translator translating words spoken by one
+person to another.
+
+In plain words:
+
+> Adapter pattern lets you wrap an otherwise incompatible object in an adapter
+to make it compatible with another class.
+
+Wikipedia says:
+
+> In software engineering, the adapter pattern is a software design pattern that
+allows the interface of an existing class to be used as another interface. It is
+often used to make existing classes work with others without modifying their
+source code.
 
 #### Programmatic Example
 
@@ -321,66 +349,200 @@ TODO
 
 #### When To Use
 
+TODO
+
 ### 🚡 Bridge
 
 #### Overview
 
+Real world example:
+
+> Consider you have a website with different pages and you are supposed to allow
+the user to change the theme. What would you do? Create multiple copies of each
+of the pages for each of the themes or would you just create separate theme and
+load them based on the user's preferences? Bridge pattern allows you to do the
+second i.e.
+
+![With and without the bridge pattern](https://cloud.githubusercontent.com/assets/11269635/23065293/33b7aea0-f515-11e6-983f-98823c9845ee.png)
+
+In plain words:
+
+> Bridge pattern is about preferring composition over inheritance.
+Implementation details are pushed from a hierarchy to another object with a
+separate hierarchy.
+
+Wikipedia says:
+
+> The bridge pattern is a design pattern used in software engineering that is
+meant to "decouple an abstraction from its implementation so that the two can
+vary independently."
+
 #### Programmatic Example
 
 TODO
 
 #### When To Use
 
+TODO
+
 ### 🌿 Composite
 
 #### Overview
 
+Real world example:
+
+> Every organization is composed of employees. Each of the employees has the
+same features i.e. has a salary, has some responsibilities, may or may not
+report to someone, may or may not have some subordinates etc.
+
+In plain words:
+
+> Composite pattern lets clients treat the individual objects in a uniform
+manner.
+
+Wikipedia says:
+
+> In software engineering, the composite pattern is a partitioning design
+pattern. The composite pattern describes that a group of objects is to be
+treated in the same way as a single instance of an object. The intent of a
+composite is to "compose" objects into tree structures to represent part-whole
+hierarchies. Implementing the composite pattern lets clients treat individual
+objects and compositions uniformly.
+
 #### Programmatic Example
 
 TODO
 
 #### When To Use
 
+TODO
+
 ### ☕ Decorator
 
 #### Overview
 
+Real world example:
+
+> Imagine you run a car service shop offering multiple services. Now how do you
+calculate the bill to be charged? You pick one service and dynamically keep
+adding to it the prices for the provided services till you get the final cost.
+Here each type of service is a decorator.
+
+In plain words:
+
+> Decorator pattern lets you dynamically change the behavior of an object at
+run time by wrapping them in an object of a decorator class.
+
+Wikipedia says:
+
+> In object-oriented programming, the decorator pattern is a design pattern that
+allows behavior to be added to an individual object, either statically or
+dynamically, without affecting the behavior of other objects from the same
+class. The decorator pattern is often useful for adhering to the Single
+Responsibility Principle, as it allows functionality to be divided between
+classes with unique areas of concern.
+
 #### Programmatic Example
 
 TODO
 
 #### When To Use
 
+TODO
+
 ### 📦 Facade
 
 #### Overview
 
+Real world example:
+
+> How do you turn on the computer? "Hit the power button" you say! That is what
+you believe because you are using a simple interface that computer provides on
+the outside, internally it has to do a lot of stuff to make it happen. This
+simple interface to the complex subsystem is a facade.
+
+In plain words:
+
+> Facade pattern provides a simplified interface to a complex subsystem.
+
+Wikipedia says:
+
+> A facade is an object that provides a simplified interface to a larger body of
+code, such as a class library.
+
 #### Programmatic Example
 
 TODO
 
 #### When To Use
 
+TODO
+
 ### 🍃 Flyweight
 
 #### Overview
 
+Real world example:
+
+> Did you ever have fresh tea from some stall? They often make more than one
+cup that you demanded and save the rest for any other customer so to save the
+resources e.g. gas etc. Flyweight pattern is all about that i.e. sharing.
+
+In plain words:
+
+> It is used to minimize memory usage or computational expenses by sharing as
+much as possible with similar objects.
+
+Wikipedia says:
+
+> In computer programming, flyweight is a software design pattern. A flyweight
+is an object that minimizes memory use by sharing as much data as possible with
+other similar objects; it is a way to use objects in large numbers when a simple
+repeated representation would use an unacceptable amount of memory.
+
 #### Programmatic Example
 
 TODO
 
 #### When To Use
 
+TODO
+
 ### 🎱 Proxy
 
 #### Overview
 
+Real world example:
+
+> Have you ever used an access card to go through a door? There are multiple
+options to open that door i.e. it can be opened either using access card or by
+pressing a button that bypasses the security. The door's main functionality is
+to open but there is a proxy added on top of it to add some functionality. Let
+me better explain it using the code example below.
+
+In plain words:
+
+> Using the proxy pattern, a class represents the functionality of another
+class.
+
+Wikipedia says:
+
+> A proxy, in its most general form, is a class functioning as an interface to
+something else. A proxy is a wrapper or agent object that is being called by the
+client to access the real serving object behind the scenes. Use of the proxy can
+simply be forwarding to the real object, or can provide additional logic. In the
+proxy extra functionality can be provided, for example caching when operations
+on the real object are resource intensive, or checking preconditions before
+operations on the real object are invoked.
+
 #### Programmatic Example
 
 TODO
 
 #### When To Use
 
+TODO
+
 ## Behavioral Design Patterns
 
 In plain words: