I thought the benefit of DLLs were that they were developed in C and were therefore a lot faster than the use of ordinary Excel macros?

I was also under the impression that in Windows you could either use the ordinary macros or DLLs. If you had something that was processor intensive and you wanted speed, then you would use DLLs. Is there an equivalent for Mac or am a wrong about the purpose of DLLs?

Cheers
Neil