From the investopedia site...
What's the difference between shares and stocks?
In today's financial markets, the distinction between stocks and shares has been somewhat blurred. Generally, these words are used interchangeably to refer to the pieces of paper that denote ownership in a particular company, called stock certificates. However, the difference between the two words comes from the context in which they are used.
For example, "stock" is a general term used to describe the shares of any company and "shares" refers to a specific stock of a particular company. So, if investors say they own stocks, they are generally referring to their overall ownership in one or more companies. If investors say they own shares - the question then becomes - shares in what company?
Bottom line, stocks and shares are the same thing. The minor distinction between stocks and shares is usually overlooked, and it has more to do with syntax than financial or legal accuracy.