iPad, iPhone, iPod, all of these items are quickly identifiable because to be Apple products because of the 'I' prefix before each name. However, as it turns out, Apple is unable to copyright that prefix - which means just about any company could use it!
The reason for this being is that when Apple applied for the patent, in the US Patents and Trademarks Office, they were denied. Apple was denied because according to the US Patent Office, you can't patent the name of something if it fits into the description of that item.
Thus, the 'I' in the names of Apple products denotes 'internet'. This means that the letter 'I' as a prefix describes the item of having internet access. Therefore the 'I' is just describing what the product is - which is something you can't put a copyright on!
Confused? It's a little more simple with the patent for the 'iPad Mini'. Apple was unable to trademark "MINI" because it describes that current model of iPad to be smaller than all the other models of the iPad. Again, they were denied because the word they tried to copyright is just descriptive!
You can't copyright words that describe your product! For example, you can't copyright the name of purple microwave if it is called "Purple microwave"