Brief History of the CLR

The CLR started around 1997. By then, COM had been around for a while and was due for a makeover. Work was begun on MTS and building a more comprehensive type system for COM+ to make COM more universally accessible from a wider array of languages. At the same time, Microsoft wanted to somehow unify the many different code management schemes. Visual Basic, FoxPro, and later J++ all had different mechanisms to manage code. Although each had its strengths and weakness, it was desirable strictly from a code-management point of view to merge the code management methodologies.

Intermediate Language (IL) specifically can trace its roots to Microsoft P-Code. A key design consideration was that the code had to be designed for compilation at the beginning. IL was never considered for a possible interpreted language. It was always assumed that this code would be compiled somehow.

As the COM3 project grew, it ended up pulling people from most of Microsoft. The name changed from COM3 to COR to COM+ 2.0 (was in parallel with COM+ 1.0) to NGWS and finally to .NET.