You can Use it On both Windows and Mac.
Let us See How to Use Whatsapp On Windows and Mac PC.
Step 1: Youwave And Bluestack Are the Two Android Emulator which enable us to Run Whatsapp or any other Android App on PC.
Step 2: If you Go for Bluestack then Download and install it, then run the Bluestack and Click
Step 3: If you Go for Youwave which I am Using On My PC then just download and install.
Enter that code and thats all.