Difference between Proxy, Decorator, Adaptor, and Bridge Patterns ?

Proxy, Decorator, Adapter, and Bridge are all variations on "wrapping" a class. But their uses are different.

• Proxy could be used when you want to lazy-instantiate an object, or hide the fact that you're calling a remote service, or control access to the object.
  See proxy pattern with details.
• Decorator is also called "Smart Proxy." This is used when you want to add functionality to an object, but not by extending that object's type. This allows you to do so at runtime.
• Adapter / Wrapper is used when you have an abstract interface, and you want to map that interface to another object which has similar functional role, but a different interface.
  In particular Decorator looks very close to Adapter but still there is basic difference:
  

  	Adapter / Wrapper	Decorator
  Composes "origin" class	True	True
  Modifies original interface	True	False
  Modifies behavior of interface	False	True
  Proxies method calls	True	True

   
  See Adapter pattern and Decorator Pattern with examples.
• Bridge is very similar to Adapter, but we call it Bridge when you define both the abstract interface and the underlying implementation. I.e. you're not adapting to some legacy or third-party code, you're the designer of all the code but you need to be able to swap out different implementations.
  See bridge pattern with example.
• Facade is a higher-level (read: simpler) interface to a subsystem of one or more classes. Think of Facade as a sort of container for other objects, as opposed to simply a wrapper. So you don't have to worry about so many things, just call the facade to do all the stuff.
  See Facade pattern with example.

Difference between Factory Pattern or Abstract Factory Pattern and Builder Pattern

Abstract factory may also be used to construct a complex object, then what is the difference with builder pattern? In builder pattern emphasis is on ‘step by step’. Builder pattern will have many number of small steps. Those every steps will have small units of logic enclosed in it. There will also be a sequence involved. It will start from step 1 and will go on upto step n and the final step is returning the object. In these steps, every step will add some value in construction of the object. That is you can imagine that the object grows stage by stage. Builder will return the object in last step. But in abstract factory how complex the built object might be, it will not have step by step object construction.

Both are creational pattern but differ:

Factory Pattern	Builder Pattern
The factor pattern defers the choice of what concrete type of object to make until run time. E.g. going to a restaurant to order the special of  the day.  The waiter is the interface to the factory that takes the abstractor generic message "Get me the special of the day!" and returns the concrete product (i.e "Chilli Paneer" or some other dish.)	The builder pattern encapsulates the logic of how to put together a complex object so that the client just requests a configuration and the builder directs the logic of building it.   E.g The main contractor (builder) in building a house knows, given a floor plan, knows how to execute the sequence of operations (i,e. by delegating to subcontractors) needed to build the complex object.  If that logic was not encapsulated in a builder, then the buyers would have to organize the subcontracting themselves
The factory is concerned with what is made.	The builder with how it is made. So it focuses on the steps of constructing the complex object.
In case of Factory or Abstract Factory, the product gets returned immediately	Builder returns the product as the final step.