SOLID Principles

What is S.O.L.I.D.? 

S.O.L.I.D. is a collection of best-practice, object-oriented design principles which can be applied to your design, allowing you to accomplish various desirable goals such as loose-coupling, 

higher maintainability, intuitive location of interesting code, etc. S.O.L.I.D. is an acronym for the following principles:

SRP: Single Responsibility Principle
THERE SHOULD NEVER BE MORE THAN ONE REASON FOR A CLASS TO CHANGE.
OCP: Open Closed Principle
SOFTWARE ENTITIES (CLASSES, MODULES, FUNCTIONS, ETC.) SHOULD BE OPEN FOR EXTENSION BUT CLOSED FOR MODIFICATION. 
LSP: Liskov Substitution Principle
FUNCTIONS THAT USE ... REFERENCES TO BASE CLASSES MUST BE ABLE TO USE OBJECTS OF DERIVED CLASSES WITHOUT KNOWING IT.
ISP: Interface Segregation Principle
CLIENTS SHOULD NOT BE FORCED TO DEPEND UPON INTERFACES THAT THEY DO NOT USE
DIP: Dependency Inversion Principle
A. HIGH LEVEL MODULES SHOULD NOT DEPEND UPON LOW LEVEL MODULES. BOTH SHOULD DEPEND UPON ABSTRACTIONS
B. ABSTRACTIONS SHOULD NOT DEPEND UPON DETAILS. DETAILS SHOULD DEPEND UPON ABSTRACTIONS

MVC 4 - Web API

Web API (application programming interface) has two main interpretations. It is used to refer to both a server-side API upon a web server as well as client-side API within a web browser.

As per Microsoft, ASP.NET Web API is a framework that makes it easy to build HTTP services that reach a broad range of clients, including browsers and mobile devices. ASP.NET Web API is an ideal platform for building RESTful applications on the .NET Framework.

You can find tutorials here.

Download eBook: ASP.Net MVC 4 and Web API

You can download HTTP Life Cycle here.

Few Learning Resources

Few online learning resources for programmers

• 5 Awesome Learning Resources For Programmers
• Programming Books
• Collection of Free Programming and Technology Related Books