Commercial Photography sells a product.
Fashion Photography sells a lifestyle.
Editorial Photography sells a story.
Now for those of you interested to learn more, please read on. Just take note that the borders between those different types of photography are fluent and may not be as distinct as I describe them here. Nonetheless, I am sure that this article will help you to easily distinguish between them. First of all let me tell you that Fashion Photography and Commercial are usually summarized in the category of Advertising Photography, while Editorial Photography tends to be a category of its own. The reason being is that both Commercial and Fashion foremost try to sell a certain product, while Editorial Photography is more concerned with a story.
Source: Svenler’s Fashion & Commercial Photography Blog