.Net framework is an integrated component of windows operating system that supports development and execution of next generation applications, Windows store apps and services.
ASP.Net Framework is used to create dynamic website, web application and web services. It is built on the top of .NET Framework.
Asp.NET Framework provides you various capabilities like Hosting Model, Site/Service Management, Protocol Abstraction, Security, Caching capability, Routing and Model Binding etc.
There are following types of asp.net sites
This is the traditional event driven development model. It has drag and drop server controls, server events and state management techniques. This best for rapid application development (RAD) with powerful data access.
2) MVC(Model View Controller)
MVC is a lightweight pattern based development model. It provides full control over mark-up and support many features that allow fast & agile development. This best for developing lightweight, interactive and device oriented (i.e. compatible to smart phones, iPhone, tablet, laptop etc.) web application with latest web standards.
3) Web Pages
This is also a lightweight and Razor syntax based development model. It has built-in template and helpers also provide full control over mark-up. It is best for developing beautiful web application with latest web standards. You can also use WebMatrix which is a free tool and has built-in template; for developing Asp.Net Web Page.
There are two ways to make Asp.Net Service
1) Web API
Asp.Net Web API is a framework for building HTTP services that can be consume by a broad range of clients including browsers, mobiles, iphone and tablets.
ASP.NET SignalR is a library that simplifies the process of adding real-time web functionality to applications. Real-time web functionality is the ability to have server code push content to connected clients instantly as it becomes available, rather than having the server wait for a client to request new data.
3-Tier Architecture in ASP.NET with C#
3-Tier architecture generally contains UI or Presentation Layer, Business Access Layer (BAL) or Business Logic Layer and Data Access Layer (DAL).
a) Presentation Layer (UI)
Presentation layer contains pages like .aspx or windows form where data is presented to the user or input is taken from the user.
2) Business Access Layer (BAL) or Business Logic Layer
BAL contains business logic, validations or calculations related with the data.
3) Data Access Layer (DAL)
DAL contains methods that helps business layer to connect the data and perform required action, might be returning data or manipulating.