CLR:Common Language RunTime.
1.A Runtime Environment Provided by Microsoft,that is usable by different Programming Language(C#,VB,F# etc..).
2.They take Care of Memory Management,Exception Handling,Assembly Loading,Threads and so on..that your Application Needs.
3.Any Code that you write with specific Compiler for Specific Language that targets CLR Ends up as Managed Module.(PE-32 -64 bit/ PE-32+ for 32 bit Exe).Managed Module Executables are intrun executed by CLR.
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