The CLR is one of the most essentialcomponent of the .Net Framework. CLR is the environment where all the programs using .Net technologies are executed. It provides service such as Code Compilation, Memory Allocation, and Garbage Collection. CLR allows the execution of code across the different platform by translating code into Intermediate Language (IL). IL is low level language that the CLR understands.
CLR consists of a set of common rules followed by all the language of the .Net framework. This set of rules is known as Common Language Specification (CLS).