You are able to attach, upload, and store any file type, including PDFs and JPGs, to the chat pane of a document, spreadsheet, or standalone chat (given that the file is less than 25MB).
FAQ: Does Quip have storage limits?
Simply put — no. As long as you have access to your Quip account you can create as many documents, spreadsheets, and chats as you need!
That being said, Quip isn't a place to store all your stuff. Quip folders are used exclusively to organize and interact with Quip documents and sheets -- not other files.
And while you can upload PDFs, images, and other assets that you might use on your computer, we don't recommend using Quip docs as the primary location to store them as individual uploads of files within docs do have certain limitations.