What is the difference between cloud computing and online storage services?

Cloud computing is the provision of services remotely i.e. not locally on your machine. Examples of this include storage, web applications, e-mail etc. Its a new concept in delivery models for IT. 'The Future' some might say. The idea being that all your 'stuff' is held 'in the cloud' in order you can access it from wherever, whenever.What is the difference between cloud computing and online storage services?
Cloud computing is basically online services where you don't really know anything about the server (where it is located, how it is implemented, etc). Online storage would be one form of cloud computing.