.NET Framework?

The Microsoft .NET Framework is a platform, for building, 
deploying, and running Web Services and applications. It 
provides a highly productive, standards-based, multi-
language environment for deployment and operation of 
Internet-scale applications. The .NET Framework consists of 
two main parts: Common Language Runtime (CLR) and the Base 
Class Libraries (BCL).

We can create 3types of application in .Net framework
1)	Windows Application
2)	Console Application
3)	Web Application



What is the common language runtime (CLR)? 

The common language runtime is the execution engine 
for .NET Framework applications. It provides a number of 
services, including the following: 
i)	Code management (loading and execution) 
ii)	Application memory isolation.
iii)	Version control.
iv)	Conversion of IL to native code.
v)	Access to metadata (enhanced type information) 
vi)	Garbage collection 
vii)	Enforcement of code access security. 
viii)	Exception handling, including cross-language 
exceptions 
ix)	Interoperation between managed code. 
x)	Support for developer services (profiling, 
debugging, and so on) 



Parts of CLR (Common Language Runtime):
1.	Common Type system (CTS)
2.	Common Language Specification (CLS)
Q: What is the common type system (CTS)? 
.Net framework supports multiple languages, and different 
language defines their primitives’ data types in different 
formats. For examples:
C# defines and integer variable		:	int i;
Where as VB.Net defines an integer variable:	Dim i as 
integer
Microsoft tries to convert these data types into a generic 
data types. So that different codes written in different 
languages code are converted into language independent 
code, due to this CTS is created.
CTS contain different data type’s specification to be used 
in our code. For example: the primitives’ integer data type 
is known as Int32, in CTS. All data types are derived from 
object data types from which the value types and reference 
types are defined.
Q: What is the Common Language Specification (CLS)? 
i)	CLS stands for Common Language Specification 
ii)	CLS is subset CTS
iii)	CLS allows developers, vendors, software 
manufactures an opportunity to work with in a common set of 
specification for language, data types.
iv)	CLS defines the standard that the object must 
contain in order to communicate with each other, in 
homogeneous environment.

clr-
   It is common Language runtime.which is Engine of .net
platform.which is responsible for execution of code,cross
language interoprebility,garbage
Collection,Security,Exception Handling.

cls(Common language specification)->set of rule which follow
by different languages
         ex-like every language used variable
declaration,exception handling,events.

cts(Common type specification) it is subset of cls.It is set
of common datatype which is used in different languages.
  ex
      VB-Integer
       C# -Int
   But cts has Int32 which is applicable for all languages.
.Framework->
      set of tools(CLR,BCL,Ado.Net etc) which used to
develop and execute an application.

What is the common language runtime (CLR)? 

The common language runtime is the execution engine 
for .NET Framework applications. It provides a number of 
services, including the following: 
i)	Code management (loading and execution) 
ii)	Application memory isolation.
iii)	Version control.
iv)	Conversion of IL to native code.
v)	Access to metadata (enhanced type information) 
vi)	Garbage collection 
vii)	Enforcement of code access security. 
viii)	Exception handling, including cross-language 
exceptions 
ix)	Interoperation between managed code. 
x)	Support for developer services (profiling, 
debugging, and so on) 



Parts of CLR (Common Language Runtime):
1.	Common Type system (CTS)
2.	Common Language Specification (CLS)
Q: What is the common type system (CTS)? 
.Net framework supports multiple languages, and different 
language defines their primitives’ data types in different 
formats. For examples:
C# defines and integer variable		:	int i;
Where as VB.Net defines an integer variable:	Dim i as 
integer
Microsoft tries to convert these data types into a generic 
data types. So that different codes written in different 
languages code are converted into language independent 
code, due to this CTS is created.
CTS contain different data type’s specification to be used 
in our code. For example: the primitives’ integer data type 
is known as Int32, in CTS. All data types are derived from 
object data types from which the value types and reference 
types are defined.
Q: What is the Common Language Specification (CLS)? 
i)	CLS stands for Common Language Specification 
ii)	CLS is subset CTS
iii)	CLS allows developers, vendors, software 
manufactures an opportunity to work with in a common set of 
specification for language, data types.
iv)	CLS defines the standard that the object must 
contain in order to communicate with each other, in 
homogeneous environment.