What is Common Language Specification (CLS) ?
Common Language Specification (CLS) is used for Language Interoperability in tandem with CTS to ensure the interoperability of the languages. CLS defines a set of minimum standards that all compilers targeting dot net must support. For example, VB.Net is not case sensitive. So attribute “EmployeeName” and “employeename” is considered same. But C# is case sensitive. So for language interoperability, C# doesn't allow two variables which differ only in case.