What is CLS ?
CLS stands for Common Language Specification. It is subset of CTS . It defines rules that governs the interoperability of languages. All .NET compliant languages should adhere to CLS .
What is CTS ?
CTS stands for Common Type System. It helps in language interoperability. It defines how to define and use types. Interger is VB.NET and int is C# is coverted to System.Int32.