Pinterest has a huge number of categories - there are already well over 30 and the number keeps growing. Five examples could include:
Popular - this category is quite simple and includes anything that people tend to like at the moment. If you click it you can find clothes, pets, quotes from authors, food items and much more.
Everything - this is like the miscellaneous category that you often find, for items that don't fit into a particular group. It is quite similar in content to the Popular category.
Videos - here people may post clips, song videos or recommendations of anything they fancy - examples of advertising, funny items off Youtube etc.
Food and drink - speaks for itself. People send pictures of their meals as well as more practical things like recipes.
Art - images, photographs, design and much more. You can send samples of your own work, something that has caught your attention online etc.
You can see the full range of Pinterest categories here.