CLR-The full name CLR is Common Language Runtime. It manages the execution of our .net programs. Our Net Program communicate with OS by CLR. Our .net Program does not communicate directly with the operating system. It is the CLR that help you to communicate with OS. It provide functionality that manages the memory management , garbage collection ,exceptional handling

MSIL-When we make our application in any language like ( C#,Vb or any other). When we compile the program it does not converted into binary. First it converted into MSIL or also known as IL (Intermediate code).Because of CLR, MSIL is untestable by CLR. Then it converted into binary called native code. MSIL act as an intermediate language. This makes cross language relationship between all the .net compliant languages.

JIT-The Full Form of JIT is Just in Time Compiler. When we compile our .net program CLR (Common Language Runtime) calls JIT compiler which is responsible for compiling IL code to native (.exe or .dll). For the specific operating System. JIT Compile the IL Code to native or binary when we need. It saves our time.

CTS-Full Form of CTS is Common type system. It allows interaction between different .net language. It Support two categories. It define rule that language must follow.it provide library that contain data type.

Value type and Reference      

Value type-It contain their data and object of value either it allocated on stack or inline.

CLS-its full form is Common language specification. CLS is a document that tell how our computer program can be turned into MSIL code when there are several languages use the same bytecode.

It is a set of basic language that .net framework needed to develop application. Common language specification gives the subset of CTS (common type system).

FCL-Its full name is Framework class library. It is a collection of library of classes, interfaces and value type. .net framework provide access to system functionality. It is the base on which application, control and component are built in .net. It provide core functionality of .net architecture. It is standard library that all .net language should use. It is integrated with CLR of the framework which manages execution.

GC-Common language runtime have garbage collector. It is also known as automatic memory manager. It provide free memory for developing new application. GC reclaim that object that have been no longer used. It Clear those memory and keep the memory free for future allocation.

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CLR IN .NET framework