Products (Products module, Ordering > Retail > Products, /admin/products) are a full retail catalogue: each product has a Short Description for lists and a long Description, images, price and cost of goods, product categories, dimensions, stock tracking, Cross Selling Products (meals or products suggested with it), and moderated Customer Reviews with title and text. They also get their own Products Dashboard. Extras are the lighter, older concept: name, price, description, images, stock - no cross-selling, no written reviews and no dashboard. Both share the same Product Categories.