Most likely your laptops webcam is having a driver problem, or worst case has become disconnected somewhere in the laptop chasis. Your best option is going to be to run windows update and include optional updates and see if your webcam starts working after all of your drivers are updated. Otherwise, check your laptop's manufacturer's website such as Asus if your brand is Asus and look up your laptops model and the driver required for it's webcam. It could also be a problem with Skype that could be fixed with a reinstallation of the application.
