Some PC-style keyboards only have one Windows key, with the right-hand equivalent being the Application key. So you only get one command key in OS X.
Fortunately, you can use Karabiner (https://pqrs.org/osx/karabiner/ - formerly known as KeyRemap4Macbook) to turn the application key into another copy of the command key.
Fortunately, you can use Karabiner (https://pqrs.org/osx/karabiner/ - formerly known as KeyRemap4Macbook) to turn the application key into another copy of the command key.