In quick summary, CATEGORIES are for products. PAGES are for content.

To explain in more detail, CATEGORIES are simply your store "aisles" which make it easier for shoppers to browse and navigate your store. Categories are for the SOLE purpose of containing PRODUCTS, or of course SUBCATEGORIES which contain PRODUCTS.

Examples of categories: CANDLES, WOOD SIGNS, POSTERS, TSHIRTS, LAMPS, etc.

PAGES on the other hand are completely different. Pages will contain INFORMATION. Exampes of PAGES are: About Me, Favorite Links, Plugboard, Vote Page, Scent Descriptions, etc.

So if you need to enter a product, you will use CATEGORIES.

If you need to enter INFORMATION, you will use PAGES.