Stuff is one of English's most versatile words, referring to things, materials, or activities when you don't need to be specific about exactly what they are.

When you say “Can you put that stuff away?” you might be pointing at toys, books, clothes, or anything else cluttering a room. When someone asks “What kind of stuff do you like to do?” they're asking about your interests and hobbies in general. A baker might gather her stuff (flour, eggs, sugar, butter) before starting a recipe.

The word can make writing feel casual and conversational, but that's also its weakness. If you write “I put stuff in my backpack,” a reader learns almost nothing. Better to say you packed your lunch, laptop, and soccer cleats. Save stuff for when the specific details don't matter or when you're talking casually with friends.

You can also stuff something, meaning to pack or fill it tightly. You might stuff a pillow with feathers, stuff papers into a folder, or stuff yourself with too much food. The noun and verb share the idea of filling space with things, whether you're talking about the things themselves or the action of cramming them in.